... is a new product after the hot-pressed and electroplated drill bit. 1. It has a super long life. ... used widely, more suitable for drilling in the stratum with hardness coefficient f<9. 6. It has a low ... for special customized sizes.9.What rock can i cut with this core bit? soft rockMudstone, shale, soft sand, peat, rock ... slate, volcanic rocks, chert, basalt, etc11,12 grade PDC drill bit (single tube)