Above: Willemite (fl. green) with quartz (non-fl.) and sphalerite (fl. orange). Quartz is rare in the ore rocks of Franklin, because the willemite used up most of the available silica.
Specimen was found on the Buckwheat in 2006.
New Jersey (together with its sister site, Sterling Hill) was home
to what may have been the most amazing mineral deposit ever found on planet
Earth. Not only did Franklin produce 350+ mineral species (a world
record, or close to it, depending on whom you ask), but it also produced
the greatest variety of fluorescent minerals known in the world. Truly,
Franklin is the Fluorescent Mineral Capital of the World.
The Franklin Mine, once an important source of zinc and manganese, closed in 1954. The shafts are sealed and the mine is flooded. Thanks to the efforts of numerous individuals, there are still one or two places where you can collect Franklin minerals (see below).
The Franklin Mineral Museum contains a great collection of minerals from the Franklin Mine, as well as specimens from the nearby Sterling Hill Mine. The museum's display collection has some of the finest examples of these minerals known. There are also some stunning mineral specimens from the rest of the world on display.
The fluorescent room at the museum has a spectacular display of Franklin minerals that glow under ultraviolet: willemite, calcite, barite, manganaxinite, margarosanite, esperite, wollastonite, and more.
Above: a vein of lilac-fluorescing scapolite along the contact between feldspar and calcite. This is another rarity from the Buckwheat.
Above: a better specimen of willemite (green) and calcite (red) from Franklin. It reminds me of Christmas lights!
Willemite is easy to identify if you have a short-wave lamp, because it fluoresces brilliant green.
Most of the Buckwheat calcite fluoresces bright red to reddish-orange in SW, but some of it responds with more of a pinkish color. There is even some calcite from here that fluoresces bluish in mid- and long-wave UV, like the Terlingua material, but it's not as bright.
Click here for more mineral photos.
Below: Another view of the Buckwheat Dump, this one taken with an old (cheap) plastic 35mm camera.
One suggestion I have for people who collect here for the first time: bring SAFETY GOGGLES, gloves, strong work boots, and a rock hammer. If you want a good rock hammer, they sell Estwing hammers and equipment at the museum gift shop. Don't use a carpenter's hammer, since its steel is more brittle and can send off shards when striking rocks.
A bricklayer's or mason's hammer is good if you don't have a rock hammer.
There are actually a lot of great specimens for the beginner all over the surface of the dump. Some of my favorite little specimens are those which were just picked up loose off the ground. Weathering and the rock cycle have already done much of the work for you.
is down behind the museum. Entrance can be
gained by paying $7 at the front desk; poundage fee is
$1.50. They open at 10 AM on weekdays and close at 4 PM; I
think on Saturdays it's 10 to 5.
The Buckwheat was originally a pile of overburden rock from the mining operation, containing material that was either devoid of zinc ore or too low in ore content to be useful. That's not to say you won't find any zinc ore there; it's just that the rock put on the Buckwheat was generally too low-grade for the refining process. A few solid chunks of ore did escape the crusher, but these are fairly uncommon.
There are many tons of Buckwheat dolomite there, which actually contained no zinc ore at all. This can however have some interesting micro minerals in it. In fact, there are at least a dozen interesting minerals in the Buckwheat dolomite alone.
Today there is still some nice stuff being found on the Buckwheat, despite the fact that the area has been collected on for many years. You can find the classic green- and red-fluorescing willemite / calcite combination there. Other fluorescent minerals are more unusual but do turn up with persistent searching. The overall number of mineral species you can find on the Buckwheat has to be around 100. Of these, I'd say there are 40-50 you have a decent chance of finding on any given day.
I have found actinolite, albite, allanite, andradite, aragonite, arsenopyrite, barite, bementite, biotite, brookite, bustamite, cerussite, chalcopyrite, clinochlore, clinohedrite, cuspidine, diopside (fluorescent and otherwise), edenite, epidote, fluorapatite, fluorite, friedelite, gahnite, galena, glaucochroite, goethite, graphite, greenockite / hawleyite, hardystonite, hematite, hemimorphite, hendricksite, hyalophane, hydrozincite, lennilenapeite, lizardite / clinochrysotile, magnesioriebeckite, magnetite, malachite, manganite / groutite / pyrolusite, meionite, microcline, monazite, norbergite, petedunnite, phlogopite, powellite / scheelite, pyrite, pyrrhotite, quartz, rhodochrosite, rhodonite, smithsonite, sphalerite, synchysite, talc, tephroite, thorite, thorutite, zincite, and several other interesting minerals on the dump... not to mention plenty of calcite, franklinite, and willemite. These are just the ones I'm reasonably sure of. I have quite a few specimens with "unidentified" labels on them. In my unverified-but-possible group I'd have to include fayalite, franklinphilite, gageite, grossular, johnbaumite, manganosite, pyrochroite, pyroxmangite, turneaureite, and something that resembles pyrochlore / microlite / samarskite.
According to at least one collector whose specialty is rare-earths, there's also been thortveitite found occasionally on the dump. That's pretty cool, because thortveitite is one of the very few minerals that contains the element Scandium (Sc).
It may take careful searching for the more serious collector to find something of interest on the surface... unless you're into micromount collecting, in which case you'll be able to find plenty.
The old timers used to claim there was "nothing good left on the Buckwheat", but this is completely untrue. What were they finding that made it so much better, esperite or something? Nobody can really answer this. The fact is, if you want to field-collect something good, you have to put in the time. There is no guarantee, just hard work and possibilities.
Franklin, New Jersey was a zinc mine. It also produced manganese and iron.
Some of the finest steel known was made from Franklin iron, because the ores contained very little sulfur. Sulfur tends to make steel brittle.
I used to have an old chisel that was labeled "silico-manganese steel". It was probably from the 1920's or 30's. I wouldn't be at all surprised if that steel originated at Franklin or Sterling Hill. Fittingly, I guess, that chisel met its end on the Buckwheat Dump. I can't remember if that one got lost or ended up shattering (because I over-hardened it), but either way, that was the last place it saw use. That little chisel lasted me a long time.
Incidentally, I noticed the new chisels they sell in stores get dull in about 2.5 seconds when trying to chisel rocks. I also noticed that I must not have the skill to harden those chisels like I used to, because after what seemed like a good round of re-shaping and re-hardening, they dulled in 2.5 seconds anyway. I did find a couple of nice willemite specimens in the process, though.
You've never seen exuberance until you've seen
100 kids who think for some reason they are going to find "gold". It
is during these times that I usually try to hide my bucket of hammers and
chisels... along with any good minerals I've found, because they tend to
get "re-found" by marauding gangs of school children.
Recently (2012) I was on the Buckwheat when an especially sophisticated group arrived. Instead of "silver" and "gold", they excitedly proclaimed finds of "calcite" and "franklinite", which was good to hear.
I have to say, though: that level of sophistication didn't diminish their excitement in the slightest. You will-- almost guaranteed-- hear the word "jackpot" about a hundred times in the space of an hour on such a day. This is what it's all about, folks: new generations discovering the great joy of rocks and minerals.
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