Gemstone, any of various minerals highly prized for beauty, durability, and rarity. A few noncrystalline materials of organic origin (e.g., pearl, red coral, and amber) also are classified as gemstones. මැණික් ගලක් යනු අලංකාරය සහ කල්පැවැත්ම ඇති පොළවෙන් මතුවන දුර්ලභ ඛනිජයකි.
A gem, or gemstone, is a type of material that is capable of being cut and polished for use in jewelry or other ornamental applications. Gems are most commonly made of minerals. Minerals, as you might already know, are naturally occurring, inorganic, crystalline solids, of definite chemical composition. There are also a few ‘gemstones’ that are actually rocks or fossils, not minerals, but we will address those later.
Most gemstones are hard, but some soft minerals are used in jewelry because of their luster or other physical properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone.
Gemstones have attracted humankind since ancient times, and have long been used for jewelry. The prime requisite for a gem is that it must be beautiful. The beauty may lie in colour or lack of colour; in the latter case, extreme limpidity and “fire” may provide the attraction.
Iridescence, opalescence, asterism (the exhibition of a star-shaped figure in reflected light), chatoyance (the exhibition of a changeable lustre and a narrow, undulating band of white light), pattern, and lustre are other features that may make a gemstone beautiful. A gem must also be durable, if the stone is to retain the polish applied to it and withstand the wear and tear of constant handling.
In addition to their use as jewelry, gems were regarded by many civilizations as miraculous and endowed with mysterious powers. Different stones were endowed with different and sometimes overlapping attributes; the diamond, for instance, was thought to give its wearer strength in battle and to protect him against ghosts and magic. Vestiges of such beliefs persist in the modern practice of wearing a birthstone.
There are many different types of gemstones, and they can be grouped based on how they are formed. Like mentioned above, gems can be formed from minerals, organic materials, other inorganic materials, or rocks (mixes of minerals, crystals, and other rocks).