- Praseolite by Webster's
(n.) A variety of altered iolite of a green color and greasy luster.
- specular hematite by Jorge Peters
(mineralogy) A variety of hematite with a blue-gray color and bright metallic luster.
- molybdenite by Daniela Manning
A mineral, molybdenum disulfide, MoS 2, blue-gray in color, with a metallic luster and greasy feel....
- Flint by Webster's
(n.) Anything extremely hard, unimpressible, and unyielding, like flint.(n.) A massive, somewhat...
- Bournonite by Webster's
(n.) A mineral of a steel-gray to black color and metallic luster, occurring crystallized, often in...