 | Edward John Chapman - 1864 - 260 lapas
...coin. Does not scratch glass (ordinary window-glass). 5. Scratches glass very feebly. Yields easily to the knife. 6. Scratches glass easily. Yields with...the knife. 7. Does not yield to the knife. Yields with difficulty to the edge of a file. 8. 9, 10. Harder than flint or rock-crystal. Convenient terms... | |
 | Josiah Samuel Phillips - 1879 - 480 lapas
...equally hard, is scratched by it. 4. Not scratched by copper; does not scratch glass. 5. Scratches glass with difficulty, leaving its powder on it. Yields...the knife. 7. Does not yield to the knife. Yields with difficulty to the edge of a file. 8. 9, 10. Harder than flint. The specific gravity is also very... | |
 | James Clarke Foye - 1882 - 108 lapas
...scratched by copper coin ; does not scratch glass. 5. — Apatite ; transparent variety. Scratches glass with difficulty, leaving its powder on it. Yields readily to the knife. 6. — Orthoclase; white cleavable variety. Scratches glass readily. Yields with difficulty to the knife.... | |
 | Frank Robertson Van Horn - 1903 - 702 lapas
...aboiit the same hardness. 4. Not scratched by a copper coin. Does not scratch glass. 5. Scratches glass with difficulty, leaving its powder on it, Yields...the knife. 6. Scratches glass easily. Yields with great difficulty to the knife. 7. Does not yield to the knife, while the latter leaves a steel streak... | |
 | Frank Robertson Van Horn - 1903 - 704 lapas
...about the same hardness. 4. Not scratched by a copper coin. Does not scratch glass. 5. Scratches glass with difficulty, leaving its powder on it. Yields readily to the knife. 260 GENERAL AND SPECIAL MINERALOGY 6. Scratches glass easily. Yields with great difficulty to the knife.... | |
 | William Hamilton Merritt - 1911 - 184 lapas
...Scratches glass with difficulty, leaving its powder on it. Yields to the knife. 6. Scratches glass readily. Yields with difficulty to the knife. 7. Does not yield to the knife. Yields to the edge of 4. Specific Gravity. — The specific gravity of a mineral is its weight as compared with the weight... | |
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Scratches a copper coin, but is also scratched by it, being aboiit the same hardness. 4. Not scratched by a copper coin. Does not scratch glass. 5. Scratches glass with difficulty, leaving its powder on it, Yields readily to the knife. 6. Scratches glass... 