Properties and Nature

The shape of emerald in its uncut state is generally hexagonal, like a six-sided prism or column. (Some experts believe that in proportion to weight, the volume of emerald is much greater; accordingly, if an emerald and a sapphire are of equal weight, the volume of the emerald will be double that of the sapphire.) It has natural cleavages on all sides. When cutting, care should be taken that only the cleavage parallel to the basal or end plane is true, while the rest are untrue. Emerald is often cut into triangular shapes and brilliant cut. (2) Its hardness ranges from 7.5 to 8 degrees; therefore, it can cut beryl/quartz. (3) Its luster is vitreous. In ancient times, its brilliance was widely renowned. Thus, Pliny writes that on the tomb of King Hermias on the island of Cyprus, there stood a marble lion with emeralds set into its eyes. Their glow shone so brightly upon the adjacent sea that the fish fled in fear and would not come near. Seeing this loss, the fishermen removed the emeralds from the eyes and replaced them with ordinary stones. Theophrastus writes that emerald is so brilliant that when placed in water, it turns the color of the water like itself. (4) The color of emerald ranges from grass green to greenish-white. (5) Its specific gravity is up to 2.678. (6) Its power of refraction is double, but of a low degree. (7) Friction can generate electrical power. (8) It is finely transparent. (9) The chemical constituents of emerald are as follows: silica 68.5 percent, alumina 15.75, glucina 12.5, iron oxide, chromium oxide 0.3, soda, magnesia 0.25, and lime. There has been debate as to which substance's composition causes emerald's color. Some researchers believe this pleasant coloration is due to chromium. Livy, by chemically analyzing an emerald from the Muzo mine in New Granada, found that a carbonate of hydrogen (a chemical union of hydrogen and carbon) is combined in it, and the depth of its color is due to this. Blum, by subjecting an emerald to intense heat for four hours and then placing it in water, found that the emerald broke into pieces; some pieces appeared black and some green. Debate continues on this point to this day, but it is generally accepted that the green color of emerald is due to chromium oxide. (10) When subjected to heat through a blowpipe or placed in acid along with borax, emerald turns yellow and melts.

Symbol ...... Two fish Date of birth ...... February 20 to March 20 Ruling planet ...... Neptune Element ...... Water Lucky days ...... Sunday, Monday, Thursday Lucky number ...... 7 Lucky stones ...... Topaz, Sapphire, and Emerald Lucky colors ...... Dark blue, Grey, White, Violet

Date of birth: January 21 to February 19 Ruling planet: Uranus Element: Air Symbol: Water bearer Favorable days: Saturday, Sunday Favorable numbers: 4, 8 Favorable stones: Agate, Turquoise, Sapphire Favorable colors: Violet, light blue, green

Ruling planet: Saturn Lucky color: Green, Brown Lucky stone: Turquoise, Sapphire Element: Earth Lucky day: Saturday Lucky number: 8

Date of Birth ......... November 23 to December 21 Ruling Planet ...... Jupiter Element ...... Fire Favorable Days ...... Friday, Thursday, Tuesday Lucky Number ...... 3 Suitable Gemstone ...... Topaz, Turquoise Favorable Colors ...... Red, Blue, and Purple Favorable Metal ......... Gold, Silver

Date of Birth ...... 23rd October Sign ...... Scorpio (Scorpion) Element ...... Water Ruling Planet ...... Pluto, Mars Lucky Number ...... 9 Lucky Day ...... Tuesday Lucky Gemstone ...... Topaz, Onyx, Opal Lucky Colors ...... Blue, Green, Red, Brown