Datolite with Chlorite

Item Description

The prizes in any highly competitive thumbnail collection are those crystals that surprise the viewer with beauty and form; and for which no larger comparable specimens are available in any case. This is a highly unusual gem crystal which dares the viewer to even guess or define the species! It is also, an amazing example of the species - Datolite. And from a classic old USA locale, that goes back to the founding days of American Mineralogy! This is USA's most famous locality for datolites known for the finest crystals but even so...this is a rarity. It is a complete-all-around, transparent colorless gem, with an unusual internal pipe or spine that could be an enclosed quartz or anhydrite, or simply a bit of matrix. However, judging by a second specimen in the collection, we believe strongly that the "faden line " is actually a slender quartz within (the second specimen Alex purchased at the same time was a larger piece, properly a small miniature, with several crystal on matrix of quartz). These specimens were both said to come from a 1948 discovery by Dr. Cliff Frondel (the famous mineralogist at Harvard), although they came out of Harvard without a label so we can only list what was passed on in the catalog. Thick edges have a green tinge due to chlorite microcrystals on some edge faces. At first, given the stunning window-clarity, gemminess, and colorlessness, most people would guess this is a phenakite or some odd topaz or beryl. Datolite is so far down my list of guesses, we would honestly not have recognized this either except that it is such a known specimen. We cannot imagine a more competitive, high ranking datolite thumbnail than this, for combination of the qualities mentioned above. When you get a thumbnail specimen, of any species, that is so far beyond expectation that it is hard to identify, that is one of the Holy Grails for us all - and a part of the challenge of owning unique things that increase the importance of all. Even if an otherwise humble species, this is a major crystal for the serious thumbnail collection.