What is Madagascar Rainbow Moonstone?

Rainbow moonstone is among the many gemstone varieties that Madagascar is known to house. Specifically, the gem is part of the feldspar mineral group within the labradorite species. Traditionally, Madagascan rainbow moonstones paired a pale bodycolor with distinctive multi-colored adularescence - the technical term describing the perceived billowing motion of the light within gems. 

It seems like the modern consumer can acquire anything they want, no matter how niche that item may be. A pair of pink gaming headphones with built-in rabbit ears? Yes, you can get them. Russian pinecone jam? It can be shipped to your home in a matter of days. We are so used to being able to find anything we please on the internet that it comes as a shock when presented with an item that truly is not available in mass quantities.

The collection of Tucson Gem Shows is an exceptional environment where, with a little bit of digging, you can find some truly singular items. At the 2025 AGTA and GJX shows, that exceptional find was a new breed of incredibly clear and vibrant rainbow moonstone from Madagascar, which, according to reports, was found in a solitary pocket within the last couple of years. 

Melchior Dollone of Nature De Colours Co., Ltd. explained that the new rainbow moonstone was unearthed in the famous Andilamena mine located in Alaotra-Mangoro. What sets this material apart from other Madagascan rainbow moonstone, he says, is its' clarity - "what is so unique about this material is that it is clean. Most other material found previously is included."

Dollone personally visited the Andilamena mine, which is situated in a small valley, and said that miners there began offering the gem to dealers about a year and a half ago. Since then, he, as well as a handful of other buyers, have been able to purchase the available inventory. In total, four dealers at the AGTA and GJX shows were identified that carried this gem, each of whom confirmed that it was their understanding that the material originated from a singular deposit. Althas Cader of Jewelmine Gems said simply, "It cannot be found anywhere else".

The gemstones at Tucson were a decent size, with most weighing at least several carats and the largest being the impressive 65.88ct cabochon at Jewelmine Gems shown above. Interestingly, Dollone said that rainbow moonstone loses quite a bit of carat weight when it is cut. "The cutting process loses lots of rough because the rainbow is usually centered on the side of the gem, rather than the top. You need lots of experience to cut it properly. If the rainbow is not perfectly centered, the gem will lose 80% of its value."

When dealers were asked if they expect more of this rainbow moonstone to emerge from Andilamena, everyone spoke cautiously. Having seen the deposit firsthand, Dollone described how miners are armed only with hand tools, and that the pit is becoming quite deep for them to handle. Joyce Dragone of Boston Gems, Inc. noted that the few available gems she has seen recently are notably smaller than the first wave of inventory. "This," she said, "does indicate to us that the mine is empty."

That is not to say that there isn't more clear rainbow moonstone, or other novel gemstones for that matter, nestled within Madagascan land. Margit Thorndal of Madagascar Imports, LTD, explained that miners have been intently focused on local deposits for the last several decades and, "they now know the geologic signs for where gems are. Who knows when the next big thing will come out!"