Composition of Gems


Various gems are in constant use, but of these, nine are claimed to be superior while eighteen of them are of lesser relevance.


  1. This is a gem of various shades of red corundum.
  2. Some stones are pink, some blackish and some pale-colored.
  3. It is a hot stone, and one of the most valued among precious stones.
  4. It generally occurs in crystals of six-sided prisms.
  5. All are translucent and suitable due to their wide range of color, and hardness.
  6. A flawless ruby is smooth, having a luster, brilliance and radiance, and a rich, red color.
  7. Rubies are very costly because of their scarcity.
  8. A large ruby is more rare and more expensive than a large diamond.
  9. The best ruby is the one which, when immersed in milk, emits red rays in the milk, or the one whose rays are red in the early morning sun, or it glows in darkness.
  10. The rare and most expensive shade is described as being the color of pigeon’s blood — a rich, velvety, deep red, but without fire or sparkle.
  11. Because rubies are more opaque than diamonds and lack sparkle and brilliance, they are cut differently.
  12. The stone is polished and cut into a convex form, but is not faceted. This is most commonly used for rubies because it accentuates the color of the gem.
  13. A blemished ruby has a depression, or a pale tinge of color, or else has sprinklings of white, black or honey-colored dots.
  14. The deepening color of ruby with time is an indication of grave danger and great personal misfortune.


  1. This is a mineral, one of the two crystalline forms of the element carbon— the drab-sounding dark substance behind the world’s most dazzling jewel —, and the hardest known substance used as a gem.
  2. It is a hot gem of white, yellow, red, pink, blue, green or black color.
  3. Unlike other gems, diamonds are prized for their absence of color. The clearer the stone, the more valuable the diamond.
  4. The diamond that is colorless, with a tinge of blue or sprays of blue and red rays, is considered to be the best, and the most common variety used in jewellery.
  5. A colored stone is called a “fancy diamond”.
  6. Clarity refers to imperfections in the stone. A diamond free of any imperfections visible under a ten-power microscope is considered flawless.
  7. A diamond is blemished if it has dots or has the impression of a drop of water.
  8. Its specific gravity is remarkably constant, the refractive index is the highest among all gemstones, and the dispersion is very strong.
  9. A hexagonal or octagonal diamond, if reflected on water, displays the seven colors of the rainbow.
  10. As for carats, a two-carat diamond can easily cost more than twice as much as a one-carat diamond.
  11. The cut of a diamond is the “C” that carries the most clout because cutting determines the diamond’s beauty and brilliance. Cutting is the spark that ignites the fire of the stone, by luring light into the gem that’s then reflected back out as sparkling brilliance.
  12. The size of the diamond is not nearly as important as the cut; a big stone is less valuable than a masterfully cut smaller one.
  13. Diamonds may be cut into round, oval, pear or emerald shapes.
  14. Round, the most popular cut, is called “brilliant” because it creates the most light.
  15. The oval, pear-shaped or emerald-shaped cuts can actually make diamonds appear larger than they are.


  1. Pearl is obtained from certain shelled mollusks, chiefly the oyster or freshwater mussel.
  2. Although organic, the pearl is composed mainly of mineral matter.
  3. Cuttured pearls are coveted for jewellery and are created by interfering with the natural process.
  4. To the untrained eye, it is impossible to tell the difference between a cultured pearl and a natural one.
  5. Natural pearls can be ten times more expensive than their cultured counterparts.
  6. Pearls, like most gems, are judged on color, and form three basic groups — white with creamy and pink being the most desirable; black and various shades of gray; and colored pearls, which are almost always of fresh water origin.
  7. The best variety is the pink one that is lustrous, clear and heavy, and is the most precious among pearls.
  8. The pure pearl is lustrous and round, though the long and the flat ones also have certain curative powers.
  9. A blemished pearl is broken, or has spots or cracks, and is dull in color.


  1. This gem is a rich variety of beryl, and the color is due to the presence of chromium oxide.
  2. It is a hot stone, and is one of the most expensive gemstones.
  3. Its colors range from a deep velvet green to a bright grass green.
  4. A flawless emerald is smooth and transparent, and has radiance and brilliance, spraying bright rays.
  5. A blemished stone has a depression or cracks, is lustrous but brittle, or has black or yellow spots with a rough surface.
  6. They are softer than diamonds, rubies or sapphires.
  7. They lack much brilliance and have virtually no fire. Because color rather than brilliance, makes emeralds valuable the convex cut is how an important emerald is usually crafted.


  1. A coral is the hard, calcareous, red, white or black skeleton of any of the various marine invertebrate animals. These skeletons collectively form reefs or islands.
  2. Its color varies from shades of red to white and yellow.
  3. A good and flawless coral will be perfectly round or oval, of an opaque red color, emitting sheen, and having a smooth surface.
  4. It is smooth, and devoid of any hole or perforation.
  5. The blemished coral has black or white spots, a depression, a crack, a bend or a twist on the surface and is sometimes multihued.
  6. The coral is worn for life and blood force.


  1. This is a transparent mineral gem, being a silicate and fluoride of aluminium, and generally found in granite rocks.
  2. It is a cold gem, occurring naturally in a prismatic form with a pyramidal termination.
  3. Its color is yellow, but it also occurs in pink and blue shades.
  4. The blemished stone has cracks, or red dots, or a depression.


  1. The blue sapphire is believed to bestow purity of purpose and deed.
  2. This is a valuable blue variety of corundum.
  3. Sapphires and rubies are actually different colors of the same mineral, corundum. But while rubies are always red, sapphires come in a variety of colors — pink, orange, violet, green, yellow, and of course, blue.
  4. It is a cold gem, with the same hardness, specific gravity and refracting indices as those of ruby.
  5. The best blue sapphire does not change its color when held in front of an electric light, while others show a navy blue tinge.
  6. It is smooth and transparent, soft to the touch, and it sends out rays from inside.
  7. The star sapphire is the “stone of destiny”, in which three crossed lines intersect in the center of the stone, symbolising faith, destiny and hope.
  8. Sapphires are believed to ward off fraud and terror, protecting one from dangers and envy.
  9. A blemished stone may have white lines on it, or a depression, or it may be dull and opaque, or else is double-colored or milky.


  1. This is a common tetragonal mineral, occurring in small, opaque or transparent prismatic crystals.
  2. Resembling a diamond, it is a cold stone.
  3. It is naturally colorless, reddish-orange, brownish-red, gray, violet-gray, or green.
  4. When heated, it turns bluish-white, and the translucent specimen is used as a gem.
  5. A good stone reflects a golden color when seen from a distance, is transparent and homogeneous, soft to the touch, lustrous and radiant.
  6. A blemished stone shows a light blackish hue from a distance, is dull, flat-bodied, full of layers, or resembles a yellow piece of glass.

Cat’s Eye

  1. This is a hard, semi-transparent variety of quartz, much valued as a gem.
  2. This very hot stone is opalescent, and is of various shades ranging from a cloudy yellow to a brownish-green color.
  3. Due to its opalescent radiation of colors that resemble a cat’s eye, it is called so.
  4. The pure variety has a yellowish radiance and a white, brilliant straight band.
  5. The blemished one has a depression, or spots, webbed lines, or a dull sheen.

The semiprecious stones of lesser reference and used as substitutes are:

  • Opal
    A mineral consisting of hydrous silica, occurring in numerous varieties and colors, neither as hard nor as dense as quartz, the finest characterised by an iridescent reflection of light. The use of opal lifts ordinary consciousness to cosmic awareness.
  • Peridot
    A precious stone of yellowish-green color
  • Tourmaline
    A complex soft silicate mineral of boron and aluminum, occurring in black, red, green, brown and white colors, the clear varieties being used as gems.
  • Amethyst
    The violet variety of quartz is used as a precious stone, containing traces of manganese, titanium and iron.
  • Rock Crystal
    A transparent quartz of a colorless or a shining white color.
  • Moonstone
    A translucent variety of feldspar with a pearly luster, and having a glistening band inside that rolls with the turn of the stone.
  • Garnet
    A hard, vitreous silicate mineral occurring in a number of varieties the common deep red transparent varieties are used as gems.
  • Aquamarine
    The finest beryl, and so-called because of its bluish, sea green, bluish-green tint and it is transparent.
  • Bloodstone
    A greenish kind of quartz with small blood-like spots of red jasper scattered through it.
  • Lapis lazuli
    A soft semiprecious stone of a rich blue color, consisting of lazurite and other minerals.
  • Agate
    A semiprecious pellucid mineral, consisting of bands or layers of various colors blended together.
  • Turquoise
    A sky blue or greenish blue mineral. It is worn for protection and is believed to purify the atmosphere of the world.
  • Jade
    A hard gemstone, either nephritic or jadeite, often green in color, either translucent or opaque, and sometimes veined.
  • Gypsum
    A mineral, a hydrous sulphate of calcium, occurring both in crystalline and massive forms.
  • Smoky quartz
    A variety of crystallised quartz, ranging in color from light yellow to deep brown.
  • Onyx
    A semi-pellucid, dark green stone with variously colored veins.
  • Carnelian
    A variety of chalcedony, of a deep red, flesh-red, or pale reddish colour.
  • Jasper
    An opaque, dark red quartz, which takes on an elegant polish.