The ruby-bearing host rocks in Pakistan are part of the Baltit group sequence and are contained in the Karakorum metamorphic belt north of the main Karakorum thrust. This meta-sedimentary unit can be traced from the Afghanistan border to the Indian border.
We visited six sites in five days in the Hunza Valley area that produce or have produced ruby. These workings are located right on the Karakoram highway on the east side of the Hunza river.
One recent discovery near the village of Bisil in the Basha Valley has the same mineral assemblage as the deposits in Hunza valley more than 100 kilometers to the west. Based on the geology and mineral assemblage at each locality the Bisil discovery is probably an eastern section of the same carbonate shelf that formed during the Eocene in the Tethys basin.
Ganesh was the northernmost spot we visited, with workings on the east side of the Hunza river. Just across the river from Ganesh, Global Mining Corp. is beginning to mine ruby-bearing marble at Gupa Nala. Another deposit is located just above the village of Aliabad. The Dhorkan workings, south of the Aliabad and Hachinder workings, are the southernmost that we visited.
Many of these deposits have the same general kinds of minerals: phlogopite, margarite and muscovite micas, zircon, spinel, magnesium tourmaline, pyrite, rutile and graphite, all of which are hosted in marbles.
Other than Global Mining Corp., we did not meet any other miners working these ruby deposits. But we could see and smell signs that explosives had been used recently, probably illegally. This is an extensive, continuous regional mineral deposit that a corporation might well be interested in working, as the presence of Global Mining Corp. indicates.
Most of the workings we visited were excavated by the Pakistan Mineral Development Corporation in the early to mid-1970s. A report on the project from 1978 states that the producing marble deposit is 2,100–3,000 meters thick and extends 25 km on strike. The average carats per ton of ruby, sapphire and red spinel from eight samples is given as 16.68 carats/long ton, with a net reserve of 161,227.97 long tons, or approximately 537.8 kg of gem material. However, there were too few samples in too few areas to come up with reliable statistics on reserves.
By Jim Clanin, geologist and gem mining expertThe ruby-bearing host rocks in Pakistan are part of the Baltit group sequence and are contained in the Karakorum metamorphic belt north of the main Karakorum thrust. This meta-sedimentary unit can be traced from the Afghanistan Border to the Indian Border.

We visited six sites in five days in the Hunza Valley area that produce or have produced ruby. These workings are located right on the Karakoram highway on the east side of the Hunza river.
One recent discovery near the village of Bisil in the Basha Valley has the same mineral assemblage as the deposits in Hunza valley more than 100 kilometers to the west. Based on the geology and mineral assemblage at each locality the Bisil discovery is probably an eastern section of the same carbonate shelf that formed during the Eocene in the Tethys basin.
Ganesh was the northernmost spot we visited, with workings on the east side of the Hunza river. Just across the river from Ganesh, Global Mining Corp. is beginning to mine ruby-bearing marble at Gupa Nala. Another deposit is located just above the village of Aliabad. The Dhorkan workings, south of the Aliabad and Hachinder workings, are the southernmost that we visited.

Many of these deposits have the same general kinds of minerals: phlogopite, margarite and muscovite micas, zircon, spinel, magnesium tourmaline, pyrite, rutile and graphite, all of which are hosted in marbles.

Other than Global Mining Corp., we did not meet any other miners working these ruby deposits. But we could see and smell signs that explosives had been used recently, probably illegally. This is an extensive, continuous regional mineral deposit that a corporation might well be interested in working, as the presence of Global Mining Corp. indicates.
Most of the workings we visited were excavated by the Pakistan Mineral Development Corporation in the early to mid-1970s. A report on the project from 1978 states that the producing marble deposit is 2,100–3,000 meters thick and extends 25 km on strike. The average carats per ton of ruby, sapphire and red spinel from eight samples is given as 16.68 carats/long ton, with a net reserve of 161,227.97 long tons, or approximately 537.8 kg of gem material. However, there were too few samples in too few areas to come up with reliable statistics on reserves.
By Jim Clanin, geologist and gem mining expert.