Inorganic Gemstones

Czochralski

Also known as the crystal pulling technique has a number of technical applications, since large crystals of good purity and optical homogeneity are obtained.

How gemstones are synthesized by czochralski process?

  • The source material is melted in a container (usually made of iridium) in an inert-gas atmosphere.
  • A rotating rod with a seed crystal is lowered until it touches the melt.
  • It is then slowly raised, allowing the molten source material, to solidify as the seed is slowly pulled from the melt.
  • The product obtained is a tabular boule which is virtually flawless.
  • Crystals which have lower melting points can be synthesized in the open, while high melting materials require a shield to control heat loss.

Gemstones synthesized by this method are:

  1. Synthetic Corundum (Synthetic Ruby and Synthetic Sapphire)
  2. Synthetic Alexandrite
  3. Yttrium Aluminium Garnet (various colours)
  4. Gadolinium Gallium Garnet (various colours)

Identification:
When present characteristic inclusions include gas bubbles, curved lines and curved colour banding. Y.A.G. and G.G.G. have characteristic properties.


Did you know?

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In Germany, the garland of ambers is hung around the necks of the infants, so that their teeth might come out without much trouble.

In Turkey, people fix a piece of amber in the hubble-bubble, dogged by an age old belief that the presence of the jewel would destroy all the germs and no disease would spread, even after many have dragged their puffs from it.

In Greece, people think if wine is poured into the cups made of amethyst, one does not get drunk after drinking that.

In Rome, a talisman having coral pieces is considered very auspicious to quell the bad spells of evil look. The Romans were in the habit of hanging chains made of ancient coral pieces from the cradle of the infants to protect them from evil effects.

In China, people wear rings studded with tiny conch or oyster shells as they believe it cures all aches such as stomach ache, worms and like.

In India, pendants made of silver and studded with pearls are hung from the necks of the children to save them from any bad effects.

Greeks still believe, if women wear blue sapphires then no sense of immorality would pollute their mind nor can any fear of the supernatural can trouble them.

The Pope Innocent III had circulated an order asking all the priests wear blue sapphire, so that morality can be strengthened.

It is said about turquoise, that when the stone changes its color into yellow, it actually signals bad times to the person who wears it.

It is believed that a turquoise gifted to a friend or a lover turns his or her life into one of happiness and good luck.

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