Ruby Land: A Museum Expedition to Mogok

by AMNH on

From the Field posts

In November 2013 a group of Museum scientists including Curators James Webster and George Harlow and Senior Scientific Assistant Jamie Newman traveled to Mogok, a historic city in northern Myanmar (Burma), to study the region's complex geological evolution on a Constantine S. Niarchos Expedition supported by the Stavros Niarchos Foundation. Read the first part of this story here. 

In Myanmar, Museum scientists worked with Dr. Kyaw Thu, a Burmese geologist, mineralogist, and gem dealer who helped arrange visits to 19 mines over 9 days in Mogok. Traveling by jeep or by foot from their home base at the Golden Butterfly Hotel, the geologists concentrated on collecting—not rubies, since these cannot be imported from Myanmar to the United States due to an embargo, but other gems and rocks to be analyzed back at the Museum.

Harlow and Webster Mogok
Museum Curators George Harlow (left) and James Webster (right) with Dr. Kyaw Thu (center) overlook the gem-rich Mogok Valley.
Image Credit: J. Newman

Most of the mines in the region are large, employing hundreds of workers and using mechanized earth-moving equipment and high-pressure hoses to blast apart the sediments from open pits. Others are more basic, but at each spot the rocks researchers collected around the mines were clues—sometimes heavy ones—to the larger context of the geology that created the gems. 

One day, for instance, they visited the Pandaw pegmatite mine. Setting off from the hotel, the team walked downhill for an hour or so on a path used for walking or, for intrepid miners, motorcycles, with birds calling in the distance through the foliage. At the bottom of the hill they finally came to a small mine, a pegmatite pocket—barely big enough for a person to wiggle into—that was mostly hand-dug.

Mogok Mine
Most of the 1,000 working mines in Mogok are industrial, but some are accessible only by remote paths.
Image Credit: J.Newman

Accompanied by miners, Harlow and Webster crawled into the mine and collected rock samples. To add to their yield, the mine owner offered them a variety of mineral and rock samples as well. Then, with full rucksacks weighing perhaps 50 pounds, the researchers slowly walked back up the track to reach their vehicle, a trek that took more than an hour. “For some reason,” says Webster, dryly, “the mines always seemed to be at the bottom of the hill.”

Geologists are used to hauling their specimens: they collect rocks on expeditions all the time. But being allowed to do so in Mogok, Myanmar, remains for Westerners a special privilege. By the end of their three-week trip, the Museum team had collected 121 kilograms (266 pounds) of rocks for studying the context of this mineral-rich area. Using X-ray diffraction, scanning electron microscopy, mass spectrometry, and other techniques back in New York, the team hopes to be able to tease out answers to Mogok’s mineralogy. 

George Harlow, James Webster and local colleagues standing before a rock face in northern Myanmar.
Harlow, Webster, and colleagues investigate the geology of Mogok. 
Image Credit: J. Newman

For instance, Harlow is working to understand how the mineral peridot—the gem form of forsterite, the common form of the mineral olivine—formed in Mogok, and whether these exquisite green gems were formed via similar processes to other known peridot deposits.

Perhaps the most important part of the trip happened not in the field, however, but in Myanmar’s universities and geological societies. There, the Museum team met and exchanged ideas with Burmese researchers who have been limited in their international collaborations and hampered in their access to modern scientific equipment. During their visit, the team met local scientists and gave presentations in Yangon and at the geology department of the University of Mandalay.

“Helping our colleagues in Myanmar and developing collaborations should be beneificial to them, the Museum, and Myanmar as well,” says Harlow. He and Webster hope that young scientists from Myanmar will be able to travel to the Museum in the not-too-distant future to train with researchers in the Department of Earth and Planetary Sciences, and that Museum postdocs will have opportunities to travel to Myanmar for field work—in Ruby Land and beyond.

This Constantine S. Niarchos Expedition was generously supported by the Stavros Niarchos Foundation.

This story is adapted from an article in the Summer 2014 issue of Rotunda, the Member magazine.