as a gemstones manufacturer and dealer, i am interested to deliver best quality stones to my clients. i am considering currently over the questions, whether it’s good to sell stones which was mined by using explosives or jackhammers. for the explosives i did read, that it can bring a stress factor in the gemstone itself, and he can probably break later easier, also if you dont see that stress from outside in the stones. how would it be for stones mined by jackhammers. also stress factor ? your opinions ?
What kind of stone are your mining or recovering? How many carats per ton of “ore” are you getting? Is your mine hard rock below ground level or is it open pit or open trench? A few photos would be nice to see. You CAN upload pics on here pretty easily. Michael in Las Vegas.
Ok I am not going into types of explosives on a public forum . But if you wish to use them for mining gems you need a slow velocity explosive. In normal hard rock blasting you would want to match the Z of your rock to the velocity of your explosive. The Z of the rock can be found by hitting the rock with a 1lb ball peen hammer. If the ball sinks in to the rock with no rebound you should just dig this rock with out explosives . On the other hand if it rockets back at you ( think granite solid granite not weathered) you have a high Z rock . But for gem mining you are not looking for max tonnage per shoot . Drill more holes and use the slowest explosive you can . Try these guys www.sierrablaster.com