2¼" demantoid garnet crystals on matrix
Specimens of andradite variety “demantoid” and variety “topazolite” have been appearing at several shows since they first debuted at the 2009 Denver Show. They are being found in a remote, muddy, tidal-flooded mangrove swamp near the village of Nosy Faly, near Antetezambato on the northern coast of Madagascar. The deposit is quite small – only about 400 by 400 meters, in which over 800 individual claims are being worked by some 2,500 people. The garnets are in a layer that is 20-40 feet below the surface. Once a shaft has been laboriously hand dug, the diggings branch out in a helter-skelter honeycomb of tunnels.
At high tide, all of the workings are completely under water, so the diggers are forced to retreat to high ground, over a mile away. Work starts as soon as the tide has receded, when the pits must be pumped out by hand, and continues at a frantic pace until the last minute before the tide comes in. The diggers fill buckets with specimens, which are hauled out of the pits, then sorted (or carried above the high tide line for later sorting). No mining can be done during the November to April rainy season.
Glassy, gemmy crystals to ¼"
The garnet crystals are generally highly lustrous dodecahedrons, and are usually about a quarter inch in size. They can be over an inch in size, but this is rare. Colors range from bright grass green (these are demantoid garnets) through yellow- and olive- green to yellowish-brown and chocolate-brown (these are topazolite). Many of the crystals are of gem quality. Most of the crystals that appear on the specimen market are found on a matrix of fine grained andradite (not limestone as was reported earlier). Matrix specimens typically range from under an inch to just over 3 inches in size. The best gem crystals are chiseled or broken off the matrix and sold to the gem trade.
Gorgeous sparkling green crystals
The specimens I acquired were carefully selected from the offerings of the dozen or so dealers who had them at Tucson this year. I only picked pieces with no damage or dings; this was not easy, as most of the available specimens had problems. This is no surprise, considering they were dug out with hammer and chisel by inexperienced diggers (not professional collectors) who were rushing to beat the incoming tide. I chose specimens with large, glassy, sparkling and gemmy crystals and brilliant facets, with good grass-green color. I especially like the ones that are so gemmy you can see matrix underneath right through the crystals.
The prospects for finding more and better specimens, now that the rainy season has ended, are uncertain. Considering the frightful digging conditions, the complete lack of safety measures, and the unknown extent of the deposit, there is certainly reason to be doubtful about future mining.
We’ve been selling specimens from this find almost as fast as we can list them. Here’s a link to the Demantoid Garnet gallery on our website, where we may have some available. If there are none shown there, you can contact us regarding availability through the About Us button on our website, www.treasuremountainmining.com.
