  The beryl is a mineral belonging to the primitive formation, and is found in quartz veins and granite. It crystallizes in six-sided prisms and is composed largely of silica, the third most common of earth’s productions. The beryl is 7.5 to 8 in hardness, scratching quartz, but is scratched by topaz. The specific gravity is 2.67 to 2.73, making it one of the light minerals. Its lustre is vitreous and refraction double to a slight degree; its cleavage is imperfectly basal, and it becomes electric by rubbing. Acids do not attack the beryl, but it melts with borax and is soluble in salts of phosphorus. This stone is found in various colors, grass-green, pale-green, light-blue, greenish-blue, greenish-yellow, yellow, and sometimes pink. The most important of these colors is the grass-green, which forms a |
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