A common black tourmaline crystal
A common black tourmaline crystal
A metamorphic crystalline rock with grains occurring in roughly parallel arrangement
Bomb-sized pyroclastic fragments, >64 mm across, formed by aerial trajections of lava
The blue, gemstone variety of corundum, Al2O3
Sedimentary rock formed through the cementation of fine grained sand
Fraudulently contaminating a mineral sample by artificially upgrading the sample to assure a more favourable result
A term used to describe the measurement of total salt content, NaCl, in water
The preparation for mining to mitigate the possibility of danger, loss and injury
A ridge having two similar elevations on either side
A geophysical study of the study of bedrock depth, or cavity location by the measuring the reflection of shockwaves induced into the ground