Gray Matter
The author creates an ornament—using his barbecue

Fire Up the Barbie By adding additional ingredients, beach sand can be melted into glass at the low, low temperature of 2,000°F. Mike Walker

All the components of glass can be found in two places: the beach and the laundry room. It’s possible to melt pure white-silica beach sand into glass, but only at temperatures of 3,000 to 3,500°F. Washing soda, lime or borax (a traditional laundry aid) added to the sand disrupts the quartz-crystal structure of silica and reduces the required temperature to a more practical, though still dangerous, 2,000°F, which I achieved with a backyard grill and a vacuum cleaner. Glass is thought to have been discovered around 7,000 years ago by Phoenician merchants when cooking fires were built over sand that, by chance, had some of these substances mixed in.

Achtung!: Theo Sez: It is very dangerous to push a charcoal grill beyond its intended temperature limits. Do not try this method of glassmaking at home. Wear a dust mask when handling silica sand.  Mike Walker
A charcoal fire fed with air from the bottom is hot enough to melt the combination of those materials into glass but not hot enough to make it truly liquid, so bubbles tend to remain and make the glass cloudy. I mixed the finely ground ingredients together and heated them in a cast-iron pot, then poured the molten glass into a graphite mold and pressed it down with a graphite stamp.

Soda-lime glass has the lowest melting point but must be cooled slowly to avoid shattering from thermal stress. Borosilicate glass, commonly known as Pyrex, melts at a higher temperature but can be cooled more rapidly. I made a medallion out of each and just left them in the fire as it died down over a few hours.

Although making glass from sand is satisfyingly primal, starting with actual glass is more practical. Old test tubes yield high-grade borosilicate glass; wine bottles, colored glass. Watch out—it’s all very sharp and hot when molten!

Click here for a slideshow of the glass-making in action. And turn the page for video.

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10 Comments

thats preeeety cool...

I'm guessing other, more widely-used methods of glass-moulding are safer and more efficient though... whatever :p

This looks way unsafe, going to give people bad ideas with this. lol.

Wow so cool!

Another use for the charcoal grill aside from grilling your steaks and lamb chops... hehehe (>,<)

that is crazy awesome would a blower work to give the fire oxygen? i really wish i could do it, it would be so cool!

Now I'm no scientist, but if you hooked up a few more vacuums and a wee bit of plutonium....

Cool experiment...I have a Weber grill just like it. How did they not melt the aluminum legs on that thing??

doggies... weber does make a good grill

why not go the whole distance and make a proper blast furnace out of high temp concrete instead of giving people unsafe ideas with a barbeque

Very interesting but very difficult to do. We use a kiln with a digital controller to make sure that the glass anneals properly at ~960 degrees C. I'd like to know if the glass ended up cracking a few days later.

glass pendant at www.trezora.com

This can also be used to instantly grill a burger!

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