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 51
Fig. 43, Fig. 44. with the sign ooR, — iR, the lower half being the sameform with the upper, but turned round 180°. In figure44, the rhombohedron mR has its polar edges replaced by … Fig. 45.
Precious stones · Building stones · Mineralogy
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