A fine Datolite specimen from a long gone Historic locality, the Bergen Hill tunnel. One of the old labels with this is handwritten and SIGNED by George Kunz, the famed mineralogist Kunz sold many minerals and built three major collections during his career but signed Kunz labels are very rare. This specimen is from the "old tunnel" in Bergen Hill, built in 1857-60. This would have been collected during that construction. A later tunnel in 1881 was dug nearby, both were important localities during the construction but not since. Specimens are now only seen in very old collections, yet this was a significant early US source of Traprock minerals. The Datolites are tiny, very lustrous sparkling crystals some of which seem to have coated earlier Pectolites. There are still numerous Pectolite crystals present especially on the backside. The Datolite seems to be formed in two different generations, most of the crystals are colorless but there is a very faint hint of color in person. Documented specimens from the "Old Tunnel" are very rare on the market.
Datolite with Quartz
Dalnegorsk, Kavalerovo Mining District
9.2 x 6.1 x 2.8 CM (cabinet)
new year 2021
Flattened habit Datolite crystals with green and yellow colors are sprinkled with Quartz crystals. The back and edges are contacted but main face is clean and very lustrous. An affordable example of a colorful Datolite from Dalnegorsk.
Datolite (color change) and Heulandite
Prospect Park Quarry, Prospect Park, Passaic County
5.1 x 3.2 x 2.8 CM (small cabinet/ large miniature)
Datolite with a strong color change from artificial to daylight, the color goes from a dark olive-green to a yellow-grey. From a remarkable pocket at the classic Prospect Park Quarry locality in 2008, there were not many pieces found. This has contrasting Huelandites with a warm brown color and shows the uncommon color change phenomenon very well. The Datolite is transparent with many faces being very glassy. There is contacting and bruising that can be hidden fairly well by display angle, so not for perfectionists. Overall the condition is equal to the best I have seen from this find, and a cute Northeastern USA oddity.
Gem clear Datolite crystals up to 2.3 CM are complexly mingled with doubly terminated "Cumberland habit" Quartz and clusters of very sharp twinned Sphalerites. It is possible to see greenish inclusions inside some Datolites. This is a rich, undamaged multi-specie specimen from Dalnegorsk, that is especially fine in person. The more this piece is examined the more remarkable details are seen. There are many good Dalnegorsk specimens available in all price ranges, this is especially fine and well worth the cost for a superior specimen.
Verhniy mine, Dalngorsk
6.5 x 6.3 x 4.4 CM (cabinet)
Post Tucson 2015
An attractive, fine specimen of older Dalngorsk Datolites. Transparent lustrous crystals with orange-brown phantoms in greenish prisms cover the matrix in an esthetic arrangement. Individual crystals are up to 2.9 CM, this sort of Datolite was rare when first found, and has not been available for several year.
San Luis Potosi,
6.4 x 6 x 3 CM (cabinet)
pre Tucson 2015 update
Great color and luster, this is a Datolite from Mexico that looks much more like a good Russian specimen. From a small find in late 2013, this has the form, clarity and quality of the top few percent. Some edge chipping/contacts is inevitable but overall in very good condition.
Impressive and a Northeastern US classic! Sharp, clear and bright gemmy Datolites up to 2.4 CM with selective faces colored a nice cognac hue sit on a contrasting green Prehnite. As esthetic as you can find, the main crystals are in perfect condition but non detracting damage is noted on a few smaller crystals and at the edges. Despite this it displays very well and is a striking specimen from this old locale.