A popular treatise on gems, in reference to their scientific value; a guide for the teacher of natural sciences, the jeweller, and amateur: together with a description of the elements of mineralogy, and all ornamental and architectural materials .. (1859)
Feuchtwanger, Lewis. [from old catalog] · New York, D. Appleton & company · leaf 31
Fig. 5. Fig. 6- 6. The icositetrahedrons (most common variety, fig. 6)are bounded by twenty-four deltoids or figures with foureides, of which two and two adjacent ones are equal. Thisform varies from the octahedron to the cube, sometimesapproaching the former and sometimes the latter in…
Precious stones · Building stones · Mineralogy
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