Last year I wrote about a very large tourmaline (4 pounds!) that I inherited from my grandfather's Maine collection. (posts 11 months ago.) The value of the crystal should vary considerably if it's a Maine crystal vs. say a Brazilian crystal. Because there is a lack of written documentation in the collection, I was curious about the issue of provenance. I received a number of useful replies, particularly as to the difference between provenance and locality origin.
My grandfather's stepson can confirm that the stone was in my grandfather's collection circa 1970. I was told by my now deceased mother that my grandfather discovered the stone (he prospected in Maine in the mid 1900's) but I'm the sole source for that information.
I've consulted with a Maine tourmaline expert, who says the stone could have come from Mt. Mica (although he can't of course confirm that.) That coincides with my own research into mining at that time, and the look of crystals from different sites.
Because of some bad experiences in the past, I'd been reluctant to share photos of the stone, but I've changed my mind. I'd be interested in your comments. I'm also going to post this in the valuation section.
Please note the comments about difficulty in capturing the color of the stone: For some reason, my cameras have difficulty getting the body color correct, showing it as too blue.
Photos 1 and 2 have been post-processed a bit to approximate the exterior color.
The green's not right ,too olivey, but the stone's exterior is not as blue as show in photos 3 and 4.
Photos 3 and 4 give a sense of the exterior's translucency
This is not a clear, gem quality, crystal. But it is not opaque; it has very pretty light reflecting qualities - which I found very difficult to photograph! In too much sun, the camera is blinded by light prisms; inside photos make the the crystal appear matte...
Jenny
I'm not sure what comments you're looking for Jenny, but that is one heck of a specimen no matter what colour it is! Definitely something to hang on to (although I'm sure there are dealers just salivating to get there hands on it).
As far as locality; Mt. Mica is always a pretty good bet, but without proper documentation it's also just a guess. Hi Paul,
Thanks for the comment. I do love it, but financial pressures force a sale.:-( Unfortunately without proper documentation of its origin it's not clear how to go about this, particularly as it's not the "classic" Maine tourmaline. One high end auction house and a private buyer said no for that reason. I picked this forum because I'd heard about new, non-invasive analytic techniques (LIBS for one) that could distinguish between a Maine or Brazil crystal.
I haven't seen any comments on this technique for a while - I think I'll start a new post with the question.
Jenny Jennifer, it is possible that using edx or similar to measure the trace element signatures of your xls will allow you to determine whether or not these specimens are from Maine by comparison with signatures from location-confirmed pieces. Maine and Brazilian samples should be distinctively different. My best guess for the tourmaline's locality would be Newry. The slightly more cool green/bluish green color is what gives me the clue to its probable Newry origin. To my recollection, the tourmalines from Mt. Mica are more of a warm green color. I don't know where you live, but if you ask the curator who works at the Maine Mineral & Gem Museum in Bethel, ME, they would probably know the specimen's exact location. Rick thank you for your comment.
I have been in touch with an expert in mineral analysis using LIBS. . Her question was whether there is a database which has trace mineral information for different tourmaline locations. She was unaware of such a database, but I have seen references such as your message, which suggests that this information exists.
Are you aware of where this information could be accessed? This would be extremely helpful to me.
Thank you so much.
Jenny Thanks Susan for your post.
Could the curator make an assessment from photos? Or would he or she need to see the crystal in person?
I live in New Hampshire comments and I have actually traveled to the main museum before, so it is possible for me to go in person.
Jenny
