Silicon carbide is one of the hardest-known materials with a Mohs Scale hardness of 9+. This hardness gives it the ability to cut tumbling roughs such as agate, jasper and petrified wood, which have a Mohs hardness of about 7.
Angular Particles: When crushed, silicon carbide breaks into angular-shaped particles with sharp points and edges. This gives it an effective cutting and grinding ability when it is caught between tumbling rocks in tumbler barrel.
Inexpensive: Silicon carbide is inexpensive, selling for just a few dollars per pound as a screened and packaged product.
The combination of hardness, angularity and low price make silicon carbide an excellent abrasive for rock tumbling, gem cutting and lapidary work of all kinds. Silicon carbide granules are also used for sand paper, sand blasting, water-jet cutting and many other purposes.
via: https://rocktumbler.com/blog/what-is-silicon-carbide-grit/
My most precious ‘stony’s’
WãshēKōdä.blog 
https://en.wikipedia.org/wiki/Silicon_carbide
semiconductor containing silicon and carbon. It occurs in nature as the extremely rare mineral moissanite. Synthetic SiC powder has been mass-produced since 1893 for use as an abrasive. Grains of silicon carbide can be bonded together by sintering to form very hard ceramics that are widely used in applications requiring high endurance, such as car brakes, car clutches and ceramic plates in bulletproof vests. Electronic applications of silicon carbide such as light-emitting diodes (LEDs) and detectors in early radios were first demonstrated around 1907. SiC is used in semiconductor electronics devices that operate at high temperatures or high voltages, or both. Large single crystals of silicon carbide can be grown by the Lely method and they can be cut into gems known as synthetic moissanite. ❗️
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Yes, totally fine grade! 🙂
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Not as much fun as the double 2 gallon tumbler 60 yrs ago but a lot quieter ❗️
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Yes, those tumblers can be LOUD!
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Tracy: My ‘National Geographic Hobby Tumbler’ is kinda quiet with a vulcanized rubber ‘drum’ 60db Inside a ‘Colman’ cooler in the back laundry room only 45db ❗️ 💎{40db in the dead of night with nothing running, all I here are my crickets (Tinnitus) 😉 } ~Willy
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😂😂😂
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I am enjoying the posts about rock tumbling. Love the necklace with the agate.
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More to come Sherry 🙂 I have 3 more batches of rough grit (silicon dioxide) to do, (got to clean everything to remove all the coerce grit, then stage 2 with 8 batches of a refining grit of SiO² for a week each. Then stage 3 a week each then stage4 using the finest polishing of SiO² running for 10 days each ❗️ 𝕊𝕥𝕒𝕪 𝕋𝕦𝕟𝕖𝕕 ~Willy
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