A crystal structure having three symmetrical sides, alone or series
A crystal structure having three symmetrical sides, alone or series
The period following the Cretaceous, from 65 to 1.8 million years ago
The period in time from 245 – 208 million years ago
Any material deposited by pyroclastic movement
The direction of defined mineralization or structure
A mineral comprised of tellurium and another element
A long, narrow excavation made to expose, access or further define mineralization
A brittle, trigonal mineral. Symbol, Te
A type of igneous rock prone to crystallization forming in cavities
To haul cars of ore or waste in a mine