when i used to pour concrete in the winter in manitoba you couldnt use direct heat from propane because it would cause spalding or flaking off of the concrete. i think you have a good idea but should have left the mortar dry naturally. time will tell . try it next time. merry christmas and a happy new year
I’ve used this cement before and it is typically dried this way. You are right that it could spall if it were a thicker coat. This is thin enough that it generally isn’t a problem. I can’t imagine pouring concrete in the winter! You’re a better person than me! Lol.
Usually in areas with freeze thaw conditions the concrete is air entrained the air entrainment allows air pockets to be formed in the concrete to help with contraction and expansion so it doesn’t break apart. the extreme heat directly on the concrete will heat up those air pockets causing the air to expand and break or explode the top off the concrete. Air entrained concrete is harder to finish since the air will cause the top to peel off on your hand trowels or power towel if you put to much down pressure on it I hate air entrained concrete lol. The refractory cement he was using probably had very little air in it so he should be ok except maybe for the lid that he moves all the time…
you have another piece left why not try making another one and let the cement cure fully before applying heat. it can be a control .when i was building chimneys you let them dry for a bit before using. just a thought. and a wrap or two of haywire around the outside.
Hi Jason! What a wonderful channel you have created! I have been hooked on chemistry and mining videos for the last while and I must say, your approach and style (all real, no bullshit fake crap) has me a dedicated subscriber!). Please keep up the great work man! So great!!!! Chris from Canada
I always overengineer, spend hundreds, weld for days and Jason nails it for pennies on the dollar! Awesome :) I have imbedded temp probes, mix vanes, special coatings, variable blowers, foot control double doors and Jasons performs just fine.
Right. I just built one out of shiny polished stainless steel, have a dozen hours into it and now I am overengeneering a pivoting lid with a cam lift system... and still not fired up . probably won't work.
This is amazing. You don't need a big expensive furnace to cast metal. I'm going to do something like this to cast bronze art pieces. Thank you so much for sharing the knowledge Jason. ~ greetings from Los Angeles
As usual, a great video! Just a recommendation: when cutting the wool a face mask is needed. The fibers are very dangerous to breathe (think asbestos). I’ve cut this a bunch and you can also use scissors, but that tends to dull them. ;) Also, this looks like it is 2” thick. Folks should know that it comes in different thicknesses. Thanks again for the video.
The difference with "high flow" and the other type of regulators is when you want a large volume of propane the non high flow regulators think there is a broken line when you really open them up, and automatically close. They really limit how much gas can be injected in the system. I believe they look for back pressure. The high flow allow you to really fire these up. Merry Christmas to you Jason.
Forgive my ignorance but how do these keep the flame from traveling back to the tank? Second question, would this burner setup work on much smaller 3 gallon and 1 gallon furnaces? I like the idea of using the tank vs small bottles. Thank you for your time.
@@robs9574 propane does not burn in the absence of adequate air or oxygen, so, normally no fire back up the gas line. If it worries you, get a back flow filter check valve usually available for oxyacetylene setups. If somehow air is in your propane tank, it's just a bomb, and will detonate at some point. Smaller furnaces will work pretty well with just venturi effect air in the mix. Adding air from some kind of blower will heat things up a lot, and is very helpful for larger spaces you are heating.
This is great. I have been at a magnesium foundry for a few months and have worked with the maintenance department some. They have to repair the pumps we use to transfer the molten magnesium from the pots to the casting molds. Anyway, they have this furnace to heat the pipes on the pumps to melt out any magnesium that cooled inside, so that they can work on it and change pipes out. I think I'm going to show them this video and build a better furnace, using this technique, for them.
I make my own furnaces as well. Keeping thermal mass low definitely important! I like to build my furnaces inside of 25 gal steel drums. Wrap kaowool on inside. Pour a thin cylinder of refractory rated to approximately 3000 F. Protects wool. Also, provides more even heat. I use almost exact same shop vac blower set up. Have been experimenting with creating a waste oil/diesel burner instead of forced air/propane but haven’t had success yet.
You could probably use the refractory cement on the brick base to fully seal the inside and have the portland cement as well that way there wont be any spills that leak out and causing a hazard to anything near the furnace.
Nice and simple. Proof positive that one needs not spend a bunch of $$$ (or AU$$$, £££, or €€€) to start smelting ore, or even recycling aluminum cans or copper wire.
@4:33 - If you're looking for a high-flow regulator, look for ones that are used for soup cookers. I'm not sure how many BTU that is, but it's all of them.
Thanks. I was looking at your similar one in a recent video and mentally doing that build in my head based on what I was seeing but it's nice to see it clearly and have bits explained. SUGGESTION - maybe include links in the description for the various products you used in case anyone isn't sure. I know it is fairly straight forward but might help some.
Yeah I always wondered how you make those things but they're made out of and how to do it thank you now I know how to do it but I'll be watching your video again to make sure I'm doing it right so thank you and merry Christmas Happy New Year I'll see you on the next one
Jason, you are just awesome. Have a great X-mas time with your beloved ones and stay safe. Thank you so much for enterteach us throughout this year. 💜💜💜💜
Hi Jason, I have a small Kaowool furnace that works great! Time for a larger one! Great video to help with construction. I use chicken wire around the small furnace instead of baling wire - gives better support. Thanks again! Merry Christmas to you & your family and the entire MBMMLLC gang. Take Care, Jim
Jason, Thanks for the demo and I hope the lined furnace lasts considerably longer than previous ones. I can’t imagine the difficulty of this back in the 1800s without propane. Merry Christmas to you and your family.
Does the refractory cement cure or dry? I know that regular portland cement uses the water it is mixed with to react and form the crystals that holds the aggregate together. I was concerned when I saw you heating the refractory cement that you might have been evaporating the water it needed for the curing reaction but I do not know if refractory cement cures like a concrete or gains its strength from a dehydration synthesis type reaction. It does strike me that if it needed water to cure you'd be left with a lot of mineral hydrate crystals in there which would decompose with the heat of the furnace anyway.
At least Rutland 211 is water cured alumina based refractory and doesn't need heat to cure. It does say "Does not require (but is stronger with) heat curing" and I assume that before this there is a minimum room-temp period of drying/curing. Depends on the refractory I guess? Some of them say let cure (react with water) for so and so many hours or days and then you can fire them up. Always read the manuals and instructions of use with construction materials.
I used to work with ceramic fibre blanket,board and cloth. we would enclose it in ceramic fibre cloth (same stuff fire blankets are made from) to give it longevity
I never miss your videos. Love to learn along with your experimentation... so awesome. Merry Christmas to you and your family🎄 (edit) I left a message on your phone and never heard a reply, so I will try email... I'm sure your a busy guy...
I think you should have let the factory cement dry for a few days before firing. Keep up the good work and you and your family have a wonderful Christmas ⛄
Hey Jason.....you da man on these builds...got a quick question for ya........do you have a small jet orifice in the 90 degree coupling on your 18" pipe, and if yes, what size....? You're my hero.....Bill
Kaowool life depends on the grade, and use conditions, the most common variety is essentially a Mullite (aluminum silicate) fiber. Mulites are a bit more sensitive to contamination and thermal cycling as they tend to recrystallize and become brittle at elevated temperatures. But, are a lot cheaper than pure Alumina or zirconia (Zircar) insulation given the nature of the materials your using a low cost disposable like your using is likely the best option in compromise
With all the splattering I have seen in your videos I was wondering if you ever take retired furnace wool and process it to recover any metal that got onto the wool from splattering melts.
Thanks Jason! I hope to see how the refractory cement holds up. I've seen Water Glass (sodium silicate) used (sprayed) on the kaowool too, and it will adhere layers of kaowool too. Were the firebricks the IFB, lightweight kind? Thanks again!
Pretty dang cool man. I might have missed this in the comments but what did you call that wool exactly? I couldn’t quite tell what you were calling it.
I'm having a problem with the flame going all the way to the nipple that comes off the regulator hose do I need some kind of special nipple or do I just need to turn up the pressure something
Is there any way you could recycle the hot air coming out the top with a heat exchanger? If you could somehow preheat the air from the shop vac, maybe it would be more efficient?
I have an assethelene regulator on mine has a presure guage on i use a small usb blower i bought on wish can run it of a power bank 😊 i use an old aircon sillender as the housing i also use cale wool but the flux eats away at it if it spills on it
Hello, i don't understand what you mean by nipple, it looks like just a 1" pipe. Is there something else that attaches to the front of the pipe? Because i didn't see it, thx.
Mine has ben waiting to have the wool sealed for over 3 years now 😂 sealing it will make it last, and you won't be breathing fibers 👍 i use rugidiser then the refractive coating .evryone hase their own methods. Thanks again
See, I've long wanted to smelt down scrap copper, aluminum, and brass that I collect during handyman projects, but a $500 furnace with hundreds more in crucibles, molds, tongs, etc. just doesn't make economic sense. This looks like a far cheaper method for hobbyist-level use, and I can weld up my own cone molds, pouring tray, and so on. Thanks, Jason! I would love it if you could post links in the description to the sources for your wool & firebrick, especially if your suppliers are willing to either give you a commission or a discount to us viewers.
Works great, would be nice to have it in a container and with more rigidizer to not have fibers release in air, still love the simplicity of his model.
You can always cut the bottom and top from a 30 or 35 gallon steel drum and weld handles on the sides if you want something that will last longer and weigh 40 times as much. Coat all the exposed wool and you're golden. You can even use the sealed end of the drum as a lid. Some people weld a piece of pipe to the sides of the pieces and slip a smaller pipe through them as a swivel. Works a treat for the hobby miner.
I think it was more dangerous w/o some kind of sealant because WHAT IF it blew or fell open while that huge flame is blowing? But I like it! What about some metal tape strips all the way around the outside to hold it tight. Like a barrel.
You know what would be a great thing to make? A flue that sits about that thing and pipes the poisonous smoke and fumes outside. Maybe made out of some old stainless steel fireplace flue tubes.The heat would make its own up draft I am pretty sure.
Lowes is having a sale on Craftsman baby vacuum cleaners which would probably work as a blower. I DON'T KNOW if they have a single output port or if they let out the air they suck in thru multiple vent holes. That would surely matter.
Encontrei um afloramento de rochas quartzo especificamente com muitos sulfetos pirita calcopirita um pó preto quw não sei o que é e algo mais com processo de triturar as rochas e torrefação dos sulfetos posso detectar algum ouro caso ele esteja presente dentro dos sulfetos?
when i used to pour concrete in the winter in manitoba you couldnt use direct heat from propane because it would cause spalding or flaking off of the concrete. i think you have a good idea but should have left the mortar dry naturally. time will tell . try it next time. merry christmas and a happy new year
I’ve used this cement before and it is typically dried this way. You are right that it could spall if it were a thicker coat. This is thin enough that it generally isn’t a problem.
I can’t imagine pouring concrete in the winter! You’re a better person than me! Lol.
Usually in areas with freeze thaw conditions the concrete is air entrained the air entrainment allows air pockets to be formed in the concrete to help with contraction and expansion so it doesn’t break apart. the extreme heat directly on the concrete will heat up those air pockets causing the air to expand and break or explode the top off the concrete. Air entrained concrete is harder to finish since the air will cause the top to peel off on your hand trowels or power towel if you put to much down pressure on it I hate air entrained concrete lol. The refractory cement he was using probably had very little air in it so he should be ok except maybe for the lid that he moves all the time…
Long lost artform
you have another piece left why not try making another one and let the cement cure fully before applying heat. it can be a control .when i was building chimneys you let them dry for a bit before using. just a thought. and a wrap or two of haywire around the outside.
Love these videos
Hi Jason! What a wonderful channel you have created! I have been hooked on chemistry and mining videos for the last while and I must say, your approach and style (all real, no bullshit fake crap) has me a dedicated subscriber!). Please keep up the great work man! So great!!!!
Chris from Canada
I feel the same way. Pure simplicity, no fluff, just functionality.
I always overengineer, spend hundreds, weld for days and Jason nails it for pennies on the dollar! Awesome :) I have imbedded temp probes, mix vanes, special coatings, variable blowers, foot control double doors and Jasons performs just fine.
Right. I just built one out of shiny polished stainless steel, have a dozen hours into it and now I am overengeneering a pivoting lid with a cam lift system... and still not fired up . probably won't work.
Jason, you're a good man. I wanted to see how you made your propane/oxygen regulator and you provided me with all the details I needed. Thanks.
this.
This is amazing. You don't need a big expensive furnace to cast metal. I'm going to do something like this to cast bronze art pieces. Thank you so much for sharing the knowledge Jason. ~ greetings from Los Angeles
As usual, a great video! Just a recommendation: when cutting the wool a face mask is needed. The fibers are very dangerous to breathe (think asbestos). I’ve cut this a bunch and you can also use scissors, but that tends to dull them. ;)
Also, this looks like it is 2” thick. Folks should know that it comes in different thicknesses.
Thanks again for the video.
I was literally thinking less than a week ago I wish Jason would make a video on a furnace!
I Have washed your channel for a while noticed you have a nice furnace seems to work really well. Thanks for this great information
The difference with "high flow" and the other type of regulators is when you want a large volume of propane the non high flow regulators think there is a broken line when you really open them up, and automatically close. They really limit how much gas can be injected in the system. I believe they look for back pressure. The high flow allow you to really fire these up. Merry Christmas to you Jason.
Forgive my ignorance but how do these keep the flame from traveling back to the tank? Second question, would this burner setup work on much smaller 3 gallon and 1 gallon furnaces? I like the idea of using the tank vs small bottles. Thank you for your time.
@@robs9574 propane does not burn in the absence of adequate air or oxygen, so, normally no fire back up the gas line. If it worries you, get a back flow filter check valve usually available for oxyacetylene setups. If somehow air is in your propane tank, it's just a bomb, and will detonate at some point. Smaller furnaces will work pretty well with just venturi effect air in the mix. Adding air from some kind of blower will heat things up a lot, and is very helpful for larger spaces you are heating.
@@larryevans7669 thank you👍
This is great. I have been at a magnesium foundry for a few months and have worked with the maintenance department some. They have to repair the pumps we use to transfer the molten magnesium from the pots to the casting molds. Anyway, they have this furnace to heat the pipes on the pumps to melt out any magnesium that cooled inside, so that they can work on it and change pipes out. I think I'm going to show them this video and build a better furnace, using this technique, for them.
I make my own furnaces as well. Keeping thermal mass low definitely important! I like to build my furnaces inside of 25 gal steel drums. Wrap kaowool on inside. Pour a thin cylinder of refractory rated to approximately 3000 F. Protects wool. Also, provides more even heat. I use almost exact same shop vac blower set up. Have been experimenting with creating a waste oil/diesel burner instead of forced air/propane but haven’t had success yet.
You need a more substantial blower than a shop vac for that.
Excellent
Simple and yet quite effective. Thanks for your explanation Jason.
You could probably use the refractory cement on the brick base to fully seal the inside and have the portland cement as well that way there wont be any spills that leak out and causing a hazard to anything near the furnace.
My wife surprised me with a long sleeve shirt with your logo:), Very cool…love your videos..Thank you😊
Nice and simple. Proof positive that one needs not spend a bunch of $$$ (or AU$$$, £££, or €€€) to start smelting ore, or even recycling aluminum cans or copper wire.
@4:33 - If you're looking for a high-flow regulator, look for ones that are used for soup cookers. I'm not sure how many BTU that is, but it's all of them.
Jason, you put out some great information that no one else does.
👍🏻👍🏻🇺🇲
I agree with you I also tried venturi and it was also weak now I have a blower from an old gas boiler and it is 100% better.
Sir what is the name of that sponge that you made a finance with
Thanks for showing us how to do this.
It’s a delight to watch your work. Thank you
Thanks. I was looking at your similar one in a recent video and mentally doing that build in my head based on what I was seeing but it's nice to see it clearly and have bits explained. SUGGESTION - maybe include links in the description for the various products you used in case anyone isn't sure. I know it is fairly straight forward but might help some.
awesome job Jason :) looks nice :)
Merry Christmas, Jason!
Yeah I always wondered how you make those things but they're made out of and how to do it thank you now I know how to do it but I'll be watching your video again to make sure I'm doing it right so thank you and merry Christmas Happy New Year I'll see you on the next one
Nice tutorial! 👌
Thank you for the upload, Jason!
Jason, you are just awesome. Have a great X-mas time with your beloved ones and stay safe. Thank you so much for enterteach us throughout this year. 💜💜💜💜
Merry Christmas Jason!
Coooool happy holidays
Happy holidays great educational video.
Hi Jason, I have a small Kaowool furnace that works great! Time for a larger one! Great video to help with construction. I use chicken wire around the small furnace instead of baling wire - gives better support. Thanks again! Merry Christmas to you & your family and the entire MBMMLLC gang. Take Care, Jim
Make sure you wear a respirator when cutting the wool
This is very useful. I'll be making one of these furnaces in spring.
Very Kewl. Thx for sharing this.
Merry Christmas brother and a happy new year
Thank you for all the great videos
Jason thanks for another great video Happy Holidays
Jason,
Thanks for the demo and I hope the lined furnace lasts considerably longer than previous ones. I can’t imagine the difficulty of this back in the 1800s without propane. Merry Christmas to you and your family.
Never seen an oil furnace, have you?
Just in time! I'm making one soon! Thank you Jason
Merry Christmas to you and your Family Sir!
That was cool. Looked simple enough. Thanks J. 👍
Awesome !!! Thanks for these videos. Really helpful for starters. I hope to do my own silver smelting in the future so these will be very helpfull
Love the video!!! I would be interested to see if the cement works. Merry Christmas!!
Merry Christmas Jason can't wait for the next one thanks for the great tutorial
Does the refractory cement cure or dry? I know that regular portland cement uses the water it is mixed with to react and form the crystals that holds the aggregate together. I was concerned when I saw you heating the refractory cement that you might have been evaporating the water it needed for the curing reaction but I do not know if refractory cement cures like a concrete or gains its strength from a dehydration synthesis type reaction. It does strike me that if it needed water to cure you'd be left with a lot of mineral hydrate crystals in there which would decompose with the heat of the furnace anyway.
At least Rutland 211 is water cured alumina based refractory and doesn't need heat to cure. It does say "Does not require (but is stronger with) heat curing" and I assume that before this there is a minimum room-temp period of drying/curing. Depends on the refractory I guess? Some of them say let cure (react with water) for so and so many hours or days and then you can fire them up. Always read the manuals and instructions of use with construction materials.
🔥FIRE in the HOLE🔥
MERRY CHRISTMAS 🎅
I used to work with ceramic fibre blanket,board and cloth. we would enclose it in ceramic fibre cloth (same stuff fire blankets are made from) to give it longevity
Wonderful tape - Thank You for sharing
Merrychristmas an happy newyear.!! Godbless
I never miss your videos. Love to learn along with your experimentation... so awesome.
Merry Christmas to you and your family🎄
(edit) I left a message on your phone and never heard a reply, so I will try email... I'm sure your a busy guy...
Love these videos
Like the blower set up i got the blanket for my furnace and ill get the cement but i need it mobile so ill get a 55gal barrel for 15 bucks mabe....
Merry Christmas to you and your
I think you should have let the factory cement dry for a few days before firing. Keep up the good work and you and your family have a wonderful Christmas ⛄
Hey Jason.....you da man on these builds...got a quick question for ya........do you have a small jet orifice in the 90 degree coupling on your 18" pipe, and if yes, what size....? You're my hero.....Bill
That k wool is amazing how it is that flexible and can withstand that high of heat.
Awesome this should work much better than just the wool six Stars sir
Kaowool life depends on the grade, and use conditions, the most common variety is essentially a Mullite (aluminum silicate) fiber. Mulites are a bit more sensitive to contamination and thermal cycling as they tend to recrystallize and become brittle at elevated temperatures. But, are a lot cheaper than pure Alumina or zirconia (Zircar) insulation given the nature of the materials your using a low cost disposable like your using is likely the best option in compromise
I just found your channel. You are my new favorite person. I am inspired. Can I come hang out with you and prospect? Merry Christmas!
Keep working. Good luck! 👍
Thanks for sharing, awsome video.
Merry Christmas
Thanks for sharing this information.
Question, do you use an orfice or straight flowing the gas into the pipe?
Does he use an orfis?
Right on Brother thanks 🎉🎉🎉🎉😊
The irony, you and I putting out a furnace build vid the same day😂
With all the splattering I have seen in your videos I was wondering if you ever take retired furnace wool and process it to recover any metal that got onto the wool from splattering melts.
Great video. Thanks for details. I see two types of Kao wool for sale. 6# and 8#. What type do you use? Thanks. Shawn.
Cool 😎 happy ho ho🎅🎅🎅
thanks👍
Salut mon ami, très bonne solution. Bravo 👌👌✨
Thanks Jason! I hope to see how the refractory cement holds up. I've seen Water Glass (sodium silicate) used (sprayed) on the kaowool too, and it will adhere layers of kaowool too. Were the firebricks the IFB, lightweight kind? Thanks again!
Could you melt brass and copper in that? Thanks
Pretty dang cool man. I might have missed this in the comments but what did you call that wool exactly? I couldn’t quite tell what you were calling it.
When using Portland cement as a base, doesn't cement explode when it gets superheated?
Jason, what's the wool brand/name? It's hard to figure out from the video. Kale/caled wool?
Kao wool
@@clayp5129 Made from Kaolin?
Kaowool
Do you use a flashback protector
I'm having a problem with the flame going all the way to the nipple that comes off the regulator hose do I need some kind of special nipple or do I just need to turn up the pressure something
Is there any way you could recycle the hot air coming out the top with a heat exchanger? If you could somehow preheat the air from the shop vac, maybe it would be more efficient?
I have an assethelene regulator on mine has a presure guage on i use a small usb blower i bought on wish can run it of a power bank 😊 i use an old aircon sillender as the housing i also use cale wool but the flux eats away at it if it spills on it
Jason is that Kao wool 2" thick x 2' wide ?
2:20 Did you say "2 Pi R or Pi D"?. Glad you cut it a little long.
Thank you for doing this! I have some samples to crush and smelt! Would love too see your facility if that’s possible to do in the future?
Dude thanks so much for that video
i wish you had my old furnace it was cast iron made from a bit of iron pipe and refactory cement it would fit a 9-liter cup man i wish you had it
Hello, i don't understand what you mean by nipple, it looks like just a 1" pipe. Is there something else that attaches to the front of the pipe? Because i didn't see it, thx.
Mine has ben waiting to have the wool sealed for over 3 years now 😂 sealing it will make it last, and you won't be breathing fibers 👍 i use rugidiser then the refractive coating .evryone hase their own methods. Thanks again
See, I've long wanted to smelt down scrap copper, aluminum, and brass that I collect during handyman projects, but a $500 furnace with hundreds more in crucibles, molds, tongs, etc. just doesn't make economic sense. This looks like a far cheaper method for hobbyist-level use, and I can weld up my own cone molds, pouring tray, and so on. Thanks, Jason! I would love it if you could post links in the description to the sources for your wool & firebrick, especially if your suppliers are willing to either give you a commission or a discount to us viewers.
Works great, would be nice to have it in a container and with more rigidizer to not have fibers release in air, still love the simplicity of his model.
You can always cut the bottom and top from a 30 or 35 gallon steel drum and weld handles on the sides if you want something that will last longer and weigh 40 times as much. Coat all the exposed wool and you're golden. You can even use the sealed end of the drum as a lid. Some people weld a piece of pipe to the sides of the pieces and slip a smaller pipe through them as a swivel. Works a treat for the hobby miner.
@@Peter_S_ Devil forge has a half millimeter thin foil.
So is there no threat of the fire heading up the pipe to the propane tank?
I think it was more dangerous w/o some kind of sealant because WHAT IF it blew or fell open while that huge flame is blowing? But I like it! What about some metal tape strips all the way around the outside to hold it tight. Like a barrel.
Thank you
Is it also for smelting copper ? Please let me know.
You know what would be a great thing to make? A flue that sits about that thing and pipes the poisonous smoke and fumes outside. Maybe made out of some old stainless steel fireplace flue tubes.The heat would make its own up draft I am pretty sure.
Lowes is having a sale on Craftsman baby vacuum cleaners which would probably work as a blower. I DON'T KNOW if they have a single output port or if they let out the air they suck in thru multiple vent holes. That would surely matter.
Using the shop vac was an idea I never came close to thinking about, thanks for the tip
very nice , you can also use adobe blocks, easy n cheap, or a ground earth pit, all good 🕳️🔥👹
Hey/Jason,.How/much/AU/did/you/get/Off/the/side/of/that/Mountain/with/the/Helo.?
That is interesting!
Have a blessed Holiday! Do you allow people to visit your facility? For ideas etc?
Can you explain your burner a little better? I’ve seen them built with mig tips to inject the propane. Does yours just flow freely through the elbow?
Encontrei um afloramento de rochas quartzo especificamente com muitos sulfetos pirita calcopirita um pó preto quw não sei o que é e algo mais com processo de triturar as rochas e torrefação dos sulfetos posso detectar algum ouro caso ele esteja presente dentro dos sulfetos?
How does do melting copper?
CLOCK WAY IS BETTER THE HOT AIR!! ❤❤❤❤❤❤