Some Minerals of the Buckwheat Dump,
Especially the Ore and Contact-Zone Rocks
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This list includes those minerals which occur in the ore tailings and / or the contact-zone or calc-silicate rocks which comprise the Buckwheat Dump at Franklin. NOTE: some of these minerals also occur in the "Buckwheat dolomite", which is listed separately.

Initially this list was supposed to be for micro-minerals, but it has come to include many of the macroscopic and fluorescent species that can be found at Buckwheat.  A few of the minerals from the Franklin Marble are also mentioned.

The "Frequency" ratings are for the overall species as found on the Buckwheat Dump.  Certain sub-varieties of a given mineral may be quite rare on the dumps.  For example, willemite on the dump is common, but blue willemite and "radiating" willemite are very rare.

ALLANITE: found as elongated, crude crystal shapes in microcline / quartz assemblages (the "pegmatites", which at Franklin often include andradite garnet and other "skarn" minerals). Can be weakly radioactive, but it's nothing compared to uraninite.  Look in the "dirty" (unattractive) microcline rocks, though it can occur in the amazonite.  Allanite appears as brown to black crystals, usually broken, in the feldspar or quartz.
Frequency:  Common

ANDRADITE is common in massive form on the dump, but once in a while you can find decent crystals of it which are a few millimeters across.  Occasionally, centimeter-sized crystals appear.
Once, I dug up a remnant of an andradite crystal that would have been four inches across.  It was badly dinged up and missing all its points, so I didn't keep it.
Frequency:  Common

ARSENIAN FLUORAPATITE:  See "FLUORAPATITE", below.

ARSENOPYRITE: occurs sometimes as silvery grains with pyrite and franklinite in the white calcite on the Buckwheat.  Also sometimes occurs in the Buckwheat dolomite.  It's uncommon. See also LOELLINGITE, below.  There are those who insist that all the silvery-colored metallic sulfides found on the Buckwheat are pyrrhotite;  this is incorrect.  Some of them clearly contain arsenic and are entirely non-magnetic even in powder form.
Frequency:  Uncommon

BEMENTITE: a light tan, micaceous or foliated mineral, bementite is very unusual on the Buckwheat Dump but does occur there. In 1998 I found one piece about the size of a small potato. Bementite weathers on the outside to resemble just about every other rock on the dump, so don't ask me how I found it!
Frequency:  Very Rare

BIOTITE (see also MANGANOPHYLLITE and HENDRICKSITE):  dark brown to black mica that occurs in the calcite associated with franklinite, willemite, and other minerals.  Fairly common on the dump.  When high in zinc and manganese, it becomes hendricksite.  Much of the ore-related black mica is probably hendricksite, while the material in the very sparse ore rocks and contact zone rocks is probably biotite.  To know for sure, though, you'd have to do some tests.
Frequency:  Common

CALCITE:  Can be white, gray, pink, orange, or dirty brown on the Buckwheat Dump.  Much, if not most of it, fluoresces a bright red-orange in short-wave UV.  Some of it fluoresces a beautiful bluish in mid-wave (MW) and long-wave (LW) UV, vaguely similar to the Terlingua-type calcites but not as intense.
Frequency:  Very Common

CUSPIDINE:  Several specimens have now been found on the Buckwheat.  The first one I know of personally was my find in the 1980's, though someone else undoubtedly ran into it before that.  I have found at least one good cuspidine specimen on the Buckwheat since, along with a few having sparse coverage. 
The fluorescent color is somewhere between yellow and orange.  In mid-wave UV (MW), cuspidine fluoresces a lilac color.
Frequency:  Very Rare

EPIDOTE:  found in the microcline assemblages and sometimes as veins in the diabase or basalt rocks ("camptonite"), though usually only in the coarser-grained material.  The massive form is common, but well-formed crystals are always worth saving.
Frequency:  Common

ESPERITE was the stuff of legend for a while.  I have found rocks that by all accounts should have had esperite in them, based on the "look" they had in daylight, but they were devoid of the prized mineral.  I had, however, heard second-hand tales of its being found on the Buckwheat.  Some of these tales turned out to be mistaken I.D.;  norbergite and powellite both fluoresce yellow, for example.  Finally, one day, I saw a photo of a specimen Scott Allen had found.  It was a genuine, no-mistaking-it specimen of esperite.  He found it on the Buckwheat.  This would have to be the first definite Buckwheat esperite I've ever seen, although if the tales are to be believed, it has come off the dump several times in the past decade.  

FLUORAPATITE: found as blue-green prismatic crystals in bustamite or hyalophane. Usually the crystals are broken, since they are quite brittle. Sometimes you'll find an intact one or two, and they can be several millimeters long. Some are "bent", probably due to plastic deformation of the rock deep in the earth.
Also found as gray, blue-gray, tan, or pinkish regions in andradite-franklinite-willemite matrix.  This mineral often fluoresces orange under SW UV.  It is most likely an arsenian variety that is not far in composition from johnbaumite, turneaureite, etc.
Frequency:  Uncommon; good fluorescent specimens are rare.

FLUORITE:  The sherry-colored "chlorophane" occurs in black ore rocks, sometimes with fluorapatite and usually with a dull-fluorescing willemite. 
Purple fluorite sometimes occurs in the white calcite rocks, but it's a lot harder to find than the sherry-colored material. 
Frequency:  Common, but good, rich specimens are uncommon to rare

FRANKLINITE: the material from the Buckwheat dump appears as grains and crystals which are generally much smaller than those at Sterling Hill.  Near-perfect octahedrons of franklinite can be found in the Buckwheat calcite, measuring about 0.5 mm to 1 mm across. The only reliable way to expose such tiny crystals, however, is with acid etching (oxalic, acetic, or dilute hydrochloric). Either that or else you must be very skillful with a needle to scrape away the calcite!
Frequency:  Very Common, but sharp, ideal crystals are rare

GAHNITE:  usually found as massive, crumbly, dark green to almost black misshapen crystals, with calcite and rhodonite.  Occasionally, sharp crystals have turned up.  I'm told that some of those "black ore" rocks that contain willemite & sphalerite actually have a matrix of massive gahnite, not franklinite.  The two minerals are both in the spinel group and both contain zinc;  I'd imagine they could grade into one another chemically.
Frequency:  Uncommon

GALENA: found as small, shiny-faced cleavage masses. Fairly unusual at Franklin. I have found galena only 3 or 4 times on the Buckwheat, usually in very small amounts.  There was one 2 1/2" chunk I recovered that was almost solid galena.  When I tried to trim it, the specimen broke into three pieces.
Small spots of galena do sometimes occur in the andradite-microcline-quartz assemblage that's home to the  pink-fluorescing meionite.
Frequency:  Rare

Left:  galena specimen found on the Buckwheat recently.  The bronze-yellow mineral in the rock is probably pyrite. Galena is actually rare at Franklin. Be sure to wash the hands after touching lead minerals such as galena.   Do not panic, though;  consider, first of all, that galena is highly insoluble in water.  It is also quite rare at Franklin.  Chances are that you will not find this mineral there unless you're purposely seeking it.

GLAUCOCHROITE:  Many times the sight-ID experts rely on assemblages, but some experts are not familiar with dump-collected rocks (instead focusing on what I call "Harvard Museum assemblages" - beautiful but cherry-picked specimens that don't represent most of what came up from the mines). 
The pinkish material that occurs in the cuspidine assemblage is almost certainly glaucochroite.  There is also glaucochroite in a dump-collected assemblage containing bustamite, andradite, hardystonite, franklinite, and willemite.  Some of this glaucochroite exhibits the characteristic color-change behavior:  pinkish under incandescent light, bluish-gray in white fluorescent light.  
Frequency: Uncommon

HEMATITE:  While common elsewhere in the world, a find of crystalline hematite on the Buckwheat is noteworthy event.  A good specimen of metallic black hematite with radiating habit was found on the dump in 2000.  The black hematite had dull red hematite on and around it.  I have another, very similar specimen I bought from the descendent of a Franklin miner.  The assemblage contains andradite and a mixture of gray and pink, manganoan calcite-dolomite that fluoresces weakly.
Frequency:  Common, but good specimens are rare

HENDRICKSITE:  This appears in my 2004 copy of Fleischer's Glossary as a valid species.  It is similar to biotite but contains zinc and usually some manganese.  Most of the purplish-black mica that occurs in the ore rocks is probably hendricksite.
Frequency:  Common

HUMITE group:  includes CHONDRODITE and NORBERGITE;  found in the marble with diopside, tremolite, graphite, and sometimes sulfide minerals (pyrrhotite, etc).  May or may not fluoresce a yellowish color in SW UV.  Most of the stuff on the dumps doesn't fluoresce that well, though I'm assuming it's because the good ones were carted off in previous years when people used to be able to drive into the dump with their cars  and fill up the trunk with Buckwheat rock.  
Frequency:  Common

HYALOPHANE is a barium feldspar that occurs with microcline, garnet, and other associations. It can fluoresce a deep magenta color SW. While it is not uncommon in massive form on the dump, well-formed crystals seem to be very rare.
Frequency:   Common

"JEFFERSONITE" is a local name for one or more of the pyroxenes (mostly augite), especially when found in weathered form.  It is common at Sterling Hill but does also occur on the Buckwheat Dump at Franklin.   The material usually called "jeffersonite" has a characteristic appearance:  crude, opaque, elongated or stubby crystals with a dull, sooty brown or black surface.   Jeffersonite is often home to interesting secondary minerals that can be seen with a loupe or microscope.
Frequency:  Uncommon

JOHNBAUMITE is an apatite-group mineral that occurs in the ore rocks.  It can be confused with the equally-rare cuspidine, since it fluoresces a similar color in SW.  There are some differences in their mid-range response.  Something that responds yellow-orange in short-wave and lilac to pale violet in mid-wave is probably cuspidine rather than johnbaumite.
Frequency:  Very Rare

LOELLINGITE: or perhaps arsenopyrite. One or both of these silvery-white metallic minerals can be found sometimes on the Buckwheat. Crystals were well-known in the Franklin deposit, so you might find a really good micro specimen or two if you comb the dump. I have one piece of "rotten" or weathered dolomite which contains either loellingite or arsenopyrite. Two tests for these minerals are (1) tiny particles are nonmagnetic, distinguishing them from pyrrhotite, and (2) freshly broken samples give off the garlic-like odor of arsenic.
The tin-white, metallic mineral that occurs in the so-called "black ore" rock (the same kind of rock that's often host to "cleiophane") is most likely loellingite.
Frequency:  Rare

MAGNETITE is easy enough to distinguish from FRANKLINITE by using a magnet, although the latter mineral is sometimes weakly magnetic.
Frequency:  Uncommon

MALACHITE or some other greenish, secondary copper mineral occurs in very small amounts as micro-spherules or coatings in ore rocks on the Buckwheat. Sometimes it is found with a blue-tarnished, metallic mineral that may be bornite or chalcopyrite.  In November 2005 I found a piece of microcline that contained epidote, galena, and what appeared to be malachite.
Frequency:  Rare

MANGANAXINITE is another mineral for which I keep searching but have not found any verified specimens from the Buckwheat.  However, in 2005 we did find a piece of non-fluorescent, massive material that very strongly resembled manganaxinite.  It had "that look" that experienced collectors often associate with Parker / Palmer material.  Even though rock from that operation was not dumped on the Buckwheat, there have been a few vaguely "Parker"-type rocks found on the dump here.
If you are lucky enough to find a red-fluorescing mineral that resembles manganaxinite, the easiest way to make sure it isn't calcite is to treat it with dilute hydrochloric acid.  Bubbles indicate calcite.  The "brief intense phosphorescence" (BIP) test can also be useful.
Frequency:  Very Rare, if it in fact occurs here

MANGANITE:  Dunn (1995) says this is very rare at Franklin.  One day on the Buckwheat I was taking apart a recalcitrant "pyroxenoid" boulder.  There was a weathered portion that contained some "jeffersonite".  In a small cavity were black, metallic, acicular crystals of what I assumed were manganite.  However, they could just as easily be GROUTITE or HAUSMANNITE.  I still have that specimen around somewhere, I hope.  The crystals didn't resemble anything I had found on Buckwheat before or since.  Aside from the characteristically Franklin matrix in which they were situated, the crystals reminded me more of something from the Harz Mountains of Germany.
Frequency:  Very Rare, whatever it is.  

MANGANOPHYLLITE:  This is not an official IMA name as far as I know.  It refers to a manganese-rich variety of biotite.  If there is also zinc, as there probably is in any mica associated with Franklin ores, it would be hendricksite rather than manganophyllite.  Hendricksite is an accepted, separate species from biotite.

MEIONITE (SCAPOLITE):  I'm operating under the assumption that marialite (the other scapolite-group member) is rare at Franklin, a fact Dr. Dunn and others have told me on several occasions. 
The most interesting meionite on the Buckwheat occurs in a certain kind of contact-zone rock near the boundary between quartz / feldspar "pegmatite" on the one side and andradite-rich skarn on the other.  This material is rare but fluoresces an eerily beautiful lilac color in short-wave UV.  I spent several weeks' worth of Buckwheat trips looking only for this kind of meionite, and I didn't find all that much of it.  A fairly powerful SW lamp is necessary to see the color well.
Meionite overall is reasonably common on the dump, but most of it doesn't fluoresce very well.  Good crystals seem to be very rare on the Buckwheat.
Frequency:  Common, but good fluorescent specimens are Rare

MICROCLINE:  The dirty, gray-green material is quite common on the dumps.  The pleasantly-colored variety known as AMAZONITE is somewhat harder to find.  Some Franklin microcline fluoresces a pale powder-blue or blue-white in SW UV, like a much paler version of margarosanite.
Frequency:  Very Common; good fluorescent specimens and rich green daylight material are uncommon

MOLYBDENITE: small, steel-gray or silvery flakes, easily mistaken for graphite
Frequency:  unknown, because it's so easily confused with graphite

MUSCOVITE: a light-green variety (unusual!) occurs in the contact-zone rocks with quartz and feldspar. This type of muscovite looks just like margarite, and to tell the truth, I can't distinguish between the two right now.
Frequency:  Uncommon

NORBERGITE is primarily a marble mineral, occurring as pale yellow-fluorescing grains, sometimes with blue-white FL diopside.  It does not occur in the ore rocks, although the late Nick Zipco once had for sale a specimen that had norbergite but looked as though it could have come from the edges of the orebody.  It was really odd, and I've never seen another like it.

PARGASITE is not normally an orebody mineral.  It occurs in the marble boulders as light green to grayish grains or crystals, although some of these may be EDENITE.  These are both amphiboles, so they will have the same general appearance and crystal form.  Visually distinguishing them can be difficult or impossible.
Some pargasite does fluoresce, although I haven't spent enough time in search of this particular mineral to know if specimens from the Buckwheat do so.

PETEDUNNITE:  A zinc pyroxene, petedunnite is not really that exciting to look at (though it has its own beauty when polished).  It is either dark, dull green or a lighter, olive-drab color.  The lighter material is an impure form of petedunnite that usually contains willemite.  This willemite occurs here as spots that fluoresce in short-wave UV to give the impression of glowing green cauliflower.  The petedunnite assemblage also contains GENTHELVITE, but this is rare and usually occurs only in specks.
Frequency:  Uncommon

PHLOGOPITE is commonly found as light brown flakes in calcite or marble assemblages on the dump.  Some of it fluoresces a dull yellow in SW UV.  Now and then you can find intact crystals of phlogophite.
Frequency:  Common

POWELLITE occurs as small, isolated specks of dull whitish-yellow to canary-yellow fluorescing material, sometimes associated with molybdenite. Powellite is very uncommon at the Buckwheat, but we've found some by digging. You probably will not find crystallized specimens of it, however, though there could be pseudomorphs after molybdenite.
Frequency:  Rare

PYRRHOTITE is a dull, bronze-yellow color with metallic or submetallic luster;  it looks like pyrite or tarnished arsenopyrite. Pyrrhotite crushed into small particles will stick to a magnet.  It also has a lower hardness than arsenopyrite.  Pyrrhotite forms crystals with a hexagonal cross-section, though I've never found any crystals at Franklin.  The massive form is pretty easy to find in the dolomite.
Frequency:  Common

SCHEELITE occurs almost exclusively in "black ore" rocks, sometimes with sphalerite and fluorapatite.  Typically there is some black willemite.  Franklin scheelite fluoresces white with a hint of yellow, suggesting molybdenum content.  Good, rich specimens worthy of display are quite rare.  Almost every specimen I've ever seen has consisted of only isolated specks of scheelite.
Frequency:  Rare

SONOLITE looks like a "pink tephroite" and is chemically similar to that mineral, though it also contains fluorine and hydroxyl ions. Sonolite would be found with zincite and franklinite, as well as tephroite.  Most of the would-be sonolite I've found has turned out to be glauchochroite or pink tephroite.  
Frequency:  unknown, probably rare.

SPHALERITE:  The best sphalerite on the dump occurs as veins of silvery-looking material running through white calcite.  This fluoresces a beautiful orange color in SW and usually LW and MW UV as well.  Some of it is also blue in LW and/or MW UV;  this is the variety known locally as "cleiophane".  The brown and oil-green varieties of sphalerite do not fluoresce.
Frequency:  Common, but good fluorescent ones are Rare

STILPNOMELANE is in the same group as lennilenapeite and franklinphilite (both of which occur on the Buckwheat). I think Dunn's monograph (1995) says most of the "stilpnomelane" at Franklin is in fact lennilenapeite or franklinphilite.  "Stilpnomelane"-like minerals may occur here as golden-brown, foliated masses which coat fracture seams in the pegmatites and the contact zone rock (the quartz / feldspar / garnet assemblages).  It is not what I'd call common, but a determined search should yield at least a micro specimen or two on any given day.
Frequency:  Uncommon