A practical handbook describing the physical characters and identification methods for gemstones, combining clear accounts of crystalline form, optical properties (reflection, refraction, dispersion, double refraction), colour and absorption effects, specific gravity, hardness and electrical behaviour with practical techniques such as refractometer use and heavy-liquid tests. It outlines cutting, weighting and nomenclature, distinguishes manufactured and imitation stones, and provides species-by-species descriptions of precious and semi-precious gems — including diamond, corundum, beryl, topaz, spinel, garnet, tourmaline, zircon, quartz and chrysoberyl — accompanied by diagrams, plates and tables of physical constants for practical reference.
