GEMSTONES are special varieties of minerals. Minerals are natural objects with definite chemical composition and numbers of crystal systems, which may give them a characteristic shape. Gemstones are essentially minerals, which when we cut and polished are transformed into gems. Gems have been defined as “objects of great beauty or worth” as precious stones, especially when we cut and polished for ornamental use.
Mineral are formed as a result of natural processes known as crystallization that individual lions present in natural solution join together to molecules of solid compound grow lager by addition of more ions. Rock solution that is liquid masses exists at high temperature deep within the earth as center of the earth, known as magma. As magma cools the individual ion that have been moving about in the magma lose energy and slow down and attract themselves to one another in regular arrangement. This regular arrangement of the ions is called Crystal Lattice.
Some crystals are formed in moderate temperature at earth surface water molecules for example joins together at atmosphere to form the crystals, called snow flakes. Evaporating sea water causes dissolved ion of Na+ andchlorite Cl- can close to enough attract one another and form solid particle of halite.
The mineral occurrence in the western Himalayas, the Karakorum and theHinu-kush seem to be directly related to the mountain building processes. The great variety in local country rocks, variations in element transfers along the fault zones, differences in metamorphic alterations and Geo-chemical conditions lead to the diversity of mineralization. Most of the minerals found in Gilgit-Baltistan come from pegmatites, Tourmaline, Beryl and aptite are good example. Corundum and Emerald owe their formation mainly to metamorphic and hydrothermal processes. The processes of formation are not however, always sharply defined.
Aquamarine and tourmaline tend to be relatively in the young pegmatities in high Himalayas. They are widely distributed in Northern Areas of Pakistan newly called (Gilgit-Baltistan), where they can reach majestic sizes and are often associated with apatitie, topaz and garnet.
The yellowish brown to honey pink topaz is found in the pegmatites aroundSkardu Valley. Rare pink to violet red topaz comes from the Katlang region inMardan district, from calcite and quartz veins in carbonate rocks.
Pakistani Emerald is found mainly in talc-carbonate schist of the Swat Valleyand its western and eastern extensions. A wedge of these schists, part of strongly deformed Tethys ocean crust in the Indus-Yarlung Tsangpo suture zone, is being pushed over the rocks of the Higher Himalayas along the Main Mantle Over-thrust. The combined metamorphism of sedimentary and oceanic volcanic rocks, together with alteration by mineralized water, is likely responsible for the formation of emerald. Pink to deep red ruby comes mainly from the metamorphic marble of Hunza valley and from northern border of the Pakistan and it is also known from the Neelum Valley inKashmir.
Mines in the Northern Areas of Pakistan!
Chumar Bakur Mine (Summyar-Nagar Valley)
Mines in Hunza Valley (Ruby, red and blue spinal, pargasite)
Haramosh Mines (famous mines in Pakistan)
Istak Nallah Mines (Tookla Mines)
Astore Mines (Mir Malik mines)
Shigar Valley Mines (Dassu and Sibdi mines)
To-day Peshawar is the main gem market for rough gemstones either produced in Pakistan or brought from Afghanistan. Some of the best mineral specimen may be purchased directly from the local producers at Gilgit orSkardu or at the mines. Lahore is major trading center for stones emanating from India. Lahore, Hyderabad and Karachi are the man main gem cutting centers. Karachi is indeed the biggest gem and jewelry trading center ofPakistan.
-Gemstones of Pakistan (Geology and Gemology) by Ali.H.Kazmi and Michael O”DONOGHUE
-PAKISTAN, minerals, mountain & majesty