MINERALS

It is quite a surprise how valuable stones such as gems are extracted from earth as just another stone. Nevertheless, the earth possesses over 4000 naturally occurred minerals that possess inorganic solids and characteristics of chemical crystals. Simple molecules form these minerals and when molten rock cools down and separates from mineral rich water, it is then understood as a typical mineral formation. These minerals form beautiful crystals and out of them are gems which are considered as the costliest.

GEMSTONES

At first, the gemstones which are uncut and unprocessed often look alike as rocks. The price tag can only be hanged to these gems when they are cut and polished and glow in brilliance and lustre.

These gems are historically divided in to Precious and Semiprecious classes. The precious class of gems are composed of different materials with higher standards than the semiprecious that highlights their beauty thus adding more value. Diamonds, Rubies, Sapphires and Emeralds continue to fall in to this class.

PRECIOUS GEMS

Diamonds – These gems are formed from Carbon atoms and considered as a very rare natural substance on earth. To successful formation of Diamonds, extreme underground high pressure is mandatory.

Rubies and Sapphires – These gems are formed of a mineral named Corundum which comprise of Aluminium Oxide.

Emeralds – These type of gems are a formation of mineral Beryl and is mixture of Beryllium, Aluminium, Silicon and Oxygen.

Precious gems are formed of the rarest natural substances to find thus explain its value.

COUNTRIES WITH GEM DEPOSITS IN THE WORLD

Most countries in the world produce various Gemstones but majority offer semiprecious gems leaving the rest of the countries in demand for precious gems thus being ranked top for their unique productions.

TOP COUNTRIES PRODUCING GEMS

Russia, Botswana, Democratic Republic of Congo, Australia, Canada, Sri Lanka, Zimbabwe, Angola, South Africa, Namibia and Sierra Leone.

Above are some of the many gem producing countries.

SRI LANKA AS A GEM PRODUCER

Exposed for bearing a competitive range of gemstones; Sri Lanka is matched with great gem producing nations as Russia, South Africa, Myanmar, Brazil and Thailand. Sri Lankan gem bearing gravels are known to be the richest in the world. The experience of Sri Lankan gem production is heavily influenced by tradition and modernization which has resulted in a harmonious and fascinating mine to market industry both domestically and internationally (exports). The growing demand of the global market for Sri Lankan gemstones is a result of a time honoured and thorough practice of traditional experiences and modern high powered techniques repetitively leading to well-balanced proportions and quality cut polish of the end product. The knowledge and experiences derived over centuries are utilized by the trading sector to match with the modern global business which ultimately produce latest fashions, trends and models. Thus, Sri Lanka stands as a proud gem seller and has become a priority option for many buyers in the gem field.

GEMS OF SRI LANKA

Around 200 minerals are classified as gemstones in the world out of which around 75 gem varieties are to be found in gem deposits of Sri Lanka. Throughout the past, Sri Lanka has been well known for its variety of gemstones available on the little island. The name “Rathna Deepa” (Island of Gemstones) from which Sri Lanka was/is known proves to be very accurate.

GEM VARIETIES FOUND IN SRI LANKA

MOST FOUND GEMS

Alexandrite, Alexandrite Cat’s Eye, Almandine Garnet, Amethyst, Aquamarine, Beryl, Blue Sapphire, Chrysoberyl, Chrysoberyl Cat’s Eye, Citrine, Hessonite Garnet, Moonstone, Orange Sapphire, Padmaraga Sapphire, Pink Sapphire, Pyrope Garnet, Rhodolite Garnet, Ruby, Spessartite Garnet, Spinel, Star Ruby, Star Sapphire, Tourmaline, Yellow Sapphire, Topaz and Zircon

• Corundum: Blue Sapphire, Ruby, Star Sapphire, Star Ruby, Yellow Sapphire, Golden Sapphire, Padparadscha and White Sapphire
• Chrysoberyl: Chrysoberyl Cat’s Eye Alexandrite and Alexandrite Cat’s Eye Chrysoberyl
• Spinel: Blue Spinel, Red Spinel and Mauve Spinel
• Topaz: White Topaz
• Beryl: Aquamarine, White Beryl and Pale Green Beryl
• Zircon: Green Zircon, Yellow Zircon, Brown Zircon and Red and Blue Zircon (Very Rare)
• Garnet: Rose Red Coloured, Red Mauve, Hessonite Garnet and Spessartite Garnet
• Tourmaline: Green and Brown Varieties
• Quartz: Yellow, Brown, Rose, White and Purple (Amethyst)
• Feldspar: Moonstone

LEAST FOUND GEMS

Sinhalite, Kornerupine, Andalusite, Apatite, Scapolite, Cordierite, Diopside, Enstatite and Taaffeite

RARELY FOUND GEMS

Axinite, Danburite, Euclase, Kyanite, Sapphirine, Dumortierite, Fibrolite and Monazite

GEM DEPOSTS OF SRI LANKA

Of the entire landmass of Sri Lanka, 25% is considered as gem bearing and are located in restrictive zones of highland/southwestern rocky zone. Secondary placer deposits are the 90% of gem mining sources accessed in Sri Lanka and are classified as Sedimentary gem deposits of residual, eluvial and alluvial. Metamorphic zones with skarn and calcium rich rocks are where the primary gem occurrences are mainly in contact.

SEDIMENTARY GEM DEPOSITS

Sedimentary gem deposits are by far the most important of all gem deposits in Sri Lanka. These type of gem deposits occur in thin layers of sand and gravel on hillsides, hilltops and river beds.

• Residual deposits: This type of deposits is in the close vicinity as on the flood plains of rivers.
  • Location: Elahera
• Eluvial deposits: This type of deposits is made identification difficult as they are found on hillslopes and flat areas.
  • Location: Pelmadulla
• Alluvial deposits: This type of deposits is the most common type distributed in Sri Lanka. These gems are well rounded grains and easily identified and also lies in two or three layers under a ground depth of 20 meters.
  • Location: Ratnapura

METAMORPHIC GEM DEPOSITS

It’s a well-known fact that most of Sri Lanka comprise of metamorphic rocks and thus most gem deposits in Sri Lanka are under this category. The areas which these deposits are located are abundant in skarn and calcium rich rocks. The skarn deposits in Sri Lanka are reported to have pure CO2 and thus the value. The chemical composition required to form aluminous gem minerals are abundance in deposits and most of the yielding’s are in the highland complex.

• Locations
• Skarn: Bakamuna
• Aluminous: Elahera