As a branch of mineralogy ‘Gemology’ refers to the study of natural, Synthetic, composite, reconstructed as well as imitation gem materials.

Any gemstone, completely manufacture by the nature (organic/inorganic origin) is known as natural gemstone.

Any gemstone, completely or partially manufacture by human being is known as synthetic gemstone. The physical and chemical properties and/or their crystal structure essentially correspond to their natural occurring counterparts (natural gemstones).

Imitation stones are completely manufacture by human being. An imitation stone imitates the colour, phenomenal effect, and appearance of natural/synthetic/composite/reconstructed gemstone without possessing their physical and chemical properties and/or their crystal structure.

Any gemstone, artificially manufacture by Composing/assembling of two or more natural gemstones/ synthetic gemstones/other minerals/any other material, known as a composite stone.

Any gem-material, artificially manufacture by melting/bonding/fusing of chips or waste of two or more natural gemstones/ synthetic gemstones/other minerals/any other material, known as a reconstructed stone.

Phenomena is an optical effect such as luster, sheen, chatoyancy, schiller, asterism, aventurescence, etc. It is a result of quantity & quality 0f reflection of light off and/or below the surface of the gemstone. Many times it increases the beauty of gemstones which can be seen in natural, synthetic, imitation, composite as well as in treated gemstones. There are a number of phenomenal gemstones, which are typically known as only because of their consisting phenomenal effect. E.g. Moonstone (sheen), Opal (play of colour), Sunstone (aventurescence), Star Ruby/Sapphire (asterism), etc.

Treatment and Enhancements are the trade practice which applied on a wide range as well as a wide grade of gem materials (natural/synthetic/Imitation/Composite/Reconstructed) to alter/improve/enhance their colour, luster, transparency, durability and/or phenomena and consequently their market value.

Astrology is the science of studying celestial bodies (planets) and consists of a number of belief systems. It describes relationship between astronomical phenomenas and events in the world.