| Rating | Solver | Clue |
|---|---|---|
| OBSIDIAN | Black stone | |
| POLYMNITE | A stone marked with dendrites and black lines, and so disposed as to represent rivers, marshes, etc. | |
| BASANITE | Lydian stone, or black jasper, a variety of siliceous or flinty slate, of a grayish or bluish black color. It is employed to test the purity of... | |
| TARTAR | ...ting essentially of crude cream of tartar, and used in marking pure cream of tartar, tartaric acid, potassium carbonate, black flux, etc., and, ... | |
| CASSITERITE | Native tin dioxide; tin stone; a mineral occurring in tetragonal crystals of reddish brown color, and brilliant adamantine luster; also massive... | |