Datolite specimen are commonly found in amygdaloidal cavities in diabase and basalt. It has been found abundantly in a wollastonite skarn deposit in Dalnegorsk, Russia and these specimens are currently available in substantial quantities and the Datolite specimens from this locality are arguably the best from any locality and occur in a substantial variety of crystal forms, colors and sizes. There are many good localities for daotlite specimens and the specimens described in the following localities is by no means exhaustive and will certainly be added to as good images from other localities become available. For yeas we Americans thought that we had a lock on the best and largest Datolite crystals but that was false pride because we knew nothing about the Datolites from Dalnegorsk. The Handbook of Minerals lists the largest know crystal as 12 cm but does not say where it came from but chances are that it came from Dalnegorsk and that larger crystals that that have been produced. Mindat currently lists a 404 localities for Datolite.
Australia
Colebrook Hill Mine, Colebrook Hill, Rosebery district, West Coast municipality, Tasmania, Australia
Datolite occurs in the Colebrook Hill mine, near Rosebery, as pale yellow-green to colourless crystals up to 20 mm across and also as crystalline masses associated with calcite, danburite, tremolite-actinolite, ferro-axinite and sulfide minerals (Bottrill and Baker, 2008: Manchester and Bottrill, in prep.). It is a late-stage mineral in the cavities in the axinite-rich skarn. It is seldom collected as it looks like quartz (which also occurs in the skarn), but I have seen some excellent specimens, perhaps worth up to $500 if they ever got on the market. The deposit is a well known Dana location for excellent axinite-(Fe). It was originally developed as a copper mine, with several open stopes and underground workings over a square km or so, but only operated briefly. It was since open by open cut and has been blasted for specimens, and there is a bit of material available still. The site is relatively inaccessible now though, a days trip through muddy, snake and leech infested, deep rainforest up a steep mountain; my last couple visits have lost half the party en route, and I have trouble getting anyone to come now. Uwe Kolitsch made though.
Austria
Bleidächer, Neukirchen am Großvenediger, Zell am See District, Salzburg, Austria
Canada
Madawaska Mine (Faraday Mine), Faraday Township, Hastings County, Ontario, Canada
This locality is listed in several mineralogy texts as producing fine crystals of Datolite, and you can see from the above images that they were correct.
Italy
Baveno, Verbano-Cusio-Ossola Province, Piedmont, Italy
A classical old locality better know for its feldspars (Baveno twins) but it also produces specimens of other minerals like Datolite, Fluorite & Babingtonite. I don't think the datolite specimens get much better than the two pictured above.
Mexico
,Charcas, Charcas Municipality, San Luis PotosÃ, Mexico
The base metal mine at Charcas is better know for its Danburite crystals but from time to time it produce fine specimens of danburite. The Datolite specimens from this locality are never abundant and good specimens from this locality are never sold cheaply. Sometimes these specimens are associated with little crystals of sulfide minerals like Chalcopyrite that make them particularly appealing to collectors.
Norway
Heggur Tunnel (Fjøra-Tafjord tunnel), Tafjord, Norddal, Fjord, Møre og Romsdal, Norway
The occurence of Datolite and other minerals in the Tafjord tunnel were first described in an article in NAGS-nytt (previous name of the Nordic magazin "Stein" ) in oct/dec. 1981. ( Knut Eldjarn, "Mineraler fra Tafjord-tunnelen", NAGS-nytt oct-dec 1981). The rocks in the region are old, deep-seated metamorphic rocks which locally host veins and cavities of minerals formed at a later stage. During tunneling to make a new road from Fjøre to Tafjord a system of veins and cavities were encountered about 1 km from the western entrance in november 1980. Veins and druses up to 30-40 cm contained large quartz crystals and crystals of feldspar (microcline/orthoclase) and later formed crystals of apophyllite and calcite. Scattered crystals and fragments of a yellow and glassy mineral were also found by one of the workers and later shown to mineral collectors from the nearby city of Ålesund and one specimen was shown to me in december 1980by a visiting collector from the area. Local collectors visited the tunnel in june 1981 and saved more material including also yellow crystals of datolite. I visited the locality later in the summer before writing the article about the locality and also collected a few specimens including one good 2 cm twinned crystal of datolite and excellent calcite crystals with inclusions of julgoldite etc. The following minerals were (visually) identified in situ and on specimens in mineral collections in Ålesund at the time: quartz crystals to near 1/2 m, orthoclase/microcline crystals to 10 cm, chlorite-group, calcite crystals to 5 cm in at least 2 generations - the last of these sometimes hosting inclusions of small flattened crystals of julgoldite(see: ), apatite was rarely seen in greenish-white crystals to 3 cm, pyrite, sphalerite, galena, apophyllite in platy, white crystals to 5 cm, hematite, laumontite, babingtonite in crystals to 2 mm and datolite in mostly single, yellow crystals and fragments of large crystals to 15 cm. Most of the datolite crystals were found loose, but a few matrix specimens were saved. The datolite crystals were unusual in being both large and very glassy and partly transparent with a nice yellow colour. Some of the fragments were faceted. No more than 30-40 crystals and larger fragments of datolite and a small number of matrix specimens of datolite were saved and some can be seen in museums and private collections in Norway.
Russia
Dalnegorsk, Dalnegorsk Urban District, Primorsky Krai, Russia
During the cold war, Russia developed a fortress economy and if they could not find deposits of minerals within their own borders that were economically competitive with deposits in other parts of the world, they made do with what they had. A prime example of this is the big open pit boron mine adjacent to the little down of Dalnegorsk only a few kilometers east of the sea of Japan. Though it was not competitive with the borate mines in the western world, it was the best the Russians could find. The deposit is a boron rich skarn, and the main boron mineral of interest is Datolite and a large mill and borate production facility was built and operated for years to process the Datolite from this deposit. Borate producers in the west would never dream of trying to produce borate products from such an impoverished source because they had available large deposits of calcium and sodium borates available to mine. But the Russians like the Americans found that during wartime when you don't have a competitive resource within your own borders you do what ever it takes to get the job done, and they got it done. In Dalnegorsk you can walk from the edge of town directly onto the benches of the big Datolite mine and as you walk the benches you can see many open pockets (the good specimens long gone of curse) and speculate on how many thousands of flats of specimens the mine has produced. What percentage of the good specimen (undoubtedly very high) were lost during routine blasting in the mine and dumped into the crushers. You can see from the images above the considerable variety of crystal forms and colors available in specimens from the mine. The mine now operates at a very low level if at all, and I am sure that if you look on a Google earth satellite map you can see the mine. It is likely to be a good place to collect daotlite crystals into the foreseeable future. On the other side of the valley above the town is a little pit known as the Danburite mine. Here Danburite was mines for a short time in hope of also extracting borate chemicals. This was not successful but it did produce some of the largest known Danburite crystals, some associated with little hexagonal looking tabular white Datolite crystals. There are a number of base metal mines also located in this large regional skarn that produce beautiful specimens of ilvaite, galena, calcite, pyrrhotite and a number of others, but these mines have nothing to do with the Boron mines other than their close proximity in the same regional skarn.
South Africa
Wessels Mine, Joe Morolong Local Municipality, John Taolo Gaetsewe District Municipality, Northern Cape, South Africa
Good datolite specimens from this locality are scarce and always find a ready home with collectors.
Spain
Errigoiti, Biscay, Basque Country, Spain
Switzerland
East slope, Le Catogne, Sembrancher, Entremont, Valais, Switzerland
USA
Roncari Quarry (Tilcon East Granby Quarry), East Granby, Hartford County, Connecticut, USA
Connecticut, Hartford Co., East Granby, Roncari quarry (Tilcon quarry)This trap rock quarry is perhaps a little better known for its prehnite specimens, but it has produced many good specimens of Datolite, many associated with prismatic quartz crystals and prehnite. The specimens from this mine are not as abundant as the Datolites from Paterson, New Jersey, probably mostly because less collecting was permitted there over the the years than at Paterson. One quarry worker/collector I knew had a large display of specimens from this quarry, at least half of them were datolite specimens, and part of a basement full of more specimens from the quarry. Several thousand specimens at least.
Hampden quarry, West Springfield, Hampden County, Massachusetts, USA
Lane & Son traprock quarries (Lane's Quarry), Westfield, Hampden County, Massachusetts, USA
Keweenaw County, Michigan, USA
The nodules of massive Datolite from the copper mines of the Keweenaw Peninsula may be unique and though they rarely exceed 12 cm, the beautiful colors and patterns that these Datolite nodules display when cut and polished often make very attractive specimens. They are so attractive that some collectors make fine collection out of nothing else. After looking at these beauties I think I need to get a few more for my collection.
{Rock Currier 2009>
Bergen Hill, Hudson County, New Jersey, USA
At one time in the late 19th and early 20th century, Datolite specimens from this locality were all the rage. Since that time this classic locality has been eclipsed many time by specimen from new and better localities. After viewing the Datolite specimens above from Dalnegorsk, Russia I don't have any urge to go out and get one of these for my collection.
Braen Quarry, Haledon, Passaic County, New Jersey, USA
Great Notch, Little Falls Township, Passaic County, New Jersey, USA
Paterson, Passaic County, New Jersey, USA
Paterson is generally better know for its Prehnite than for its Datolite specimens. But Datolite specimens are abundant in the amygdaloids in the basalts at this locality. Some of them are surprisingly good but shrink considerably when viewed against the Datolite specimens from Dalnegorsk, Russia, For several generations this quarry has produced thousands of Datolite specimens but the quarry is pretty small compared to the Datolite mine at Dalnegorsk. In my youth I was able to collect good specimens of datolite and prehnite when ever I could wangle permission to collect in the quarry. Hundreds of collectors over the years have collected here and no few mineral dealers have cut their teeth with specimens from this quarry. On a good afternoon I have heard the old timers saying that they could drive a pick up truck into the quarry and in a few hours load it up with Prehnite specimens.
Upper New Street Quarry, Paterson, Passaic County, New Jersey, USA
Millington Quarry, Bernards Township, Somerset County, New Jersey, USA
Fanwood Quarry (Weldon Quarry), Watchung, Somerset County, New Jersey, USA
Knippa Quarry (Whites mines; Texas Traprock quarries; Traprock Hill), Knippa, Uvalde County, Texas, USA
Lewis River, Skamania County, Washington, USA
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