Huge Monazites

Recent finds from a newly-opened REM pegmatite in the Baringer Hill Pegmatite District of central Texas. The brick-red specimens are all thorium enriched monazite, and are strongly radioactive. The dark specimen at the upper left side of the picture is samarskite, and is even more radioactive than the monazite. The large monazite nodule is actually several intergrown crystals, each about the size of a blackboard eraser, weighing more than 2-1/2 kilograms. Other minerals found at this new site (so far) are orange spessartine garnet, usually found as trapezohedra up to tennis ball size, smoky quartz, magnetite, hematite, biotite, muscovite, fluorite, uraninite, perthite, microcline and green beryl. The beryl is usually found as partial crystals. Some of these are hexagonal cross-section fragments of large hexagonal prisms up to 8 cm between opposite faces. I think I now know what my weekends are going to be like for the next few years.

Frank

Good LORD.

Color me green.

I'd dig it!

Speaking of GREEN.....

Two nearly perfect monazite terminations displaying tabular monoclinic habit. The 41.73 gram specimen on the right is a penetration twin. The one on the left weighs in at 44.73 grams. Both were found in a crystal pocket on Saturday, September 9th.

Frank

Frank....I've ALWAYS said Llano & Burnet Co.s were not sufficiently prospected.. ...you've just proven it!!!....great work!!!!

When will you get to Mason Co.????

Don S.

Thanks Don,

I might be able to get into Mason County sometime in my next life. So many pegs, so little time. BTW, here are a couple of the garnets from the new site.

Frank

Frank....that part of the world contains such unique mineralogy...it's a shame there's no BLM land in the central mineral district of Texas (ONE of the many reasons I left Texas and came to New Mexico....but I certainly miss the pegs!!!!

BTW, I haven't received your assays yet....still having problems w/ the USPS???

If so, forget the radioactives and just send the sulphides....if you'd like some lead foil (analytical grade), I'll send some....I'll get it back eventually!!!

Sorry Don, I got so caught up in the new pegmatite that I completely forgot about your package. It's been sitting in my office for weeks waiting to be sealed and shipped. That works in your favor however. I'll slip in a nice monazite with the rest of the stuff in the box. I already have some lead sheeting, which is a good thing because there's no way this stuff will ship without some shielding. BTW, I have to take ten days of vacation before the end of the month. It's cooled off somewhat here in Texas. Do you feel like heading east?

Frank

P.S. If you look at the locality index for monazite, you'll notice that it hasn't been reported in Texas before. I talked with some of the Prof's at UT Geology and one or two mentioned finding a few scattered sand grains of it in Honey Creek, North of Packsaddle Mountain, but all agreed that this find is going to rewrite a few Geology textbooks.

I could have sworn I read something about monazite from Barringer Hill / Llano area in Texas. That dates back to the late 1800's, before it was sent to the bottom of a reservoir...

Hi Fred,

Yes, monazite has been mentioned in association with the Baringer Hill Pegmatite, but so far as I am aware, only in the negative.

" It is interesting to note that among the numerous minerals in this dike no tourmaline, zircon, beryl, monazite, cassiterite, garnet, or tungsten minerals have been found. Cassiterite has been reported from the neighborhood, but its occurrence is extremely doubtful."

Hess, F. L., Minerals of the rare-earth metals at Baringer Hill, Llano County, Texas: U.S. Geol. Survey Bull. 340, pp. 286-294, 1908.

The funny thing is, the list of minerals that Frank Hess notes as being absent from Baringer Hill could almost sub for a list of the minerals that I AM finding in this new pegmatite. For obvious reasons, I cannot yet divulge the exact location of this site, but I can tell you that it is within two miles or so of the Baringer Hill locality.

In the meantime, here is a pic of one of the pieces of samarskite I pulled from a spoil pile a couple of weeks ago.

Frank

Hallo Franklin,
a new source is always a good news. Congratulations!
Here in Spain, we have some pegmatite areas with nice crystals. "Huge" signifies for us as big as an apple or something alike. Your specimens seem not to be very good crystalized, or haven't you shown your best pieces? With regard to Monazite, a heavy mineral, it is known for its conchoidal fracture that your specimens do not display. Further it is known to appear as: coarse spathic, primary occurrences in granites, syenites and gneiss, secondary deposits in placer sands (monazite-sands) (comp.: [www.a-m.de]).
In any case, be careful with radioactivity and keep reporting of that new site.
Greetings
Carlos

I'll try to post some pictures of some of the better crystalline pieces. The pic of the two I'm holding in my hand actually look a lot better than the photo would suggest. That photo, along with the photo with the cabbage-sized piece were taken with my Nikon D50 in fading light using a macro lens. That macro has a narrow enough depth of field without using it in low light conditions. Two other "excuses" for the poor photo quality, I was shooting one-handed and the specimens had yet to me washed. Usually when these things come out of the pegmatite, they're dirty and iron-stained.

Many of the larger nodules I've collected do exhibit a feathery conchoidal fracture. This material does seem to exhibit an almost perfect basal cleavage. Several pieces actually look as if they were slabbed with a diamond saw and polished. These are about 1cm thick with parallel adamantine cleavage faces and pyramidal terminations.

I share your concern about the radioactivity. So far, I have collected about 15kg of this material. It now sits in my back yard, in a thick steel container under 30cm of water with 30cm of water on all sides. Even so, at 3m I am reading about 40 uR/hr with a 50cm NaI(Tl) scintillation probe. I may have to start storing my finds in a secure container at the collecting site or expect a visit from the men in the yellow space suits.

Frank

If you obtain any complete crystals from the peg, I am definitely interested in a possible trade, although I am sure that they would be in need of lead foil for transport through any of the mailing routes that they would need to travel to get to me...

Hi Ray,

If you had asked about trading specimens a couple of weeks ago, they'd be in your collection already. Last Thursday, the situation with the new pegmatite changed dramatically. The "pros from Dover" are on their way. Two of the country's best known pegmatologists will be visiting the new site beginning next week. I had contacted them in the hopes of getting an academic team to participate in the excavation of the pegmatite from the beginning. Too often, the professionals are brought on board only after a mining operation had torn up a pegmatite and destroyed valuable formations and contextual clues. This time, the eggheads will be directing the dig from the get-go.

How does that affect me, you ask? No mineral specimens will be released to the collecting community until they have been logged, photographed and released for distributon. I guess they don't want any potential new minerals to get away from them. When these specimens are released, they will most likely be offered for sale, either through Mindat Auctions or through a separate web site that I'll set up in the near future. I would rather use this material as trading stock to build up my own collection, but I need to consider the practical aspects of the partnerhip I've entered into with the property owner. I will have to cover the day-to-day expenses such as equipment rental, lease payments, tools, gas, etc. out of my own pocket. Unless I can recover some of these costs, this new pegmatite will have to remain unexplored.

If you, or anyone else reading this would be interested in acquiring some of the material from this new site, drop me a line at Baringerhill@Yahoo.com and I'll let you know when new specimens become avalable. Right now, I'm under instructions to hold onto every scrap of material from this peg until the guys with letters after their names can have a look-see.

Frank

Well , Frank , I thank you for the heads up on the ongoing situation at the site. Sounds like you have taken a righteous course of action in the name of education and learning. I laud that approach, even if it means I don't get any complete crystals from the locale. I know of at least one peg in Northern prairie provinces in Canada that had many similar and very radioactive minerals in it. The locale was so rich in radioactives that eventually it forced a stoppage of the mining process as the rads were too high to be safe for the miners there. Hopefully that won't be the case at your site.

Actually, the rad levels are much lower here than in some of the other sites I've worked. The monazites are found scattered throughout the spoil material removed from the excavation and represent point sources of radiation. Even with a sensitive scintillation detector, the probe has to pass within a foot or so of a buried specimen to register the hot spot. If the whole site was hot, I wouldn't have been able to detect the monazite signatures in the high background.

As to the possibility of procuring a complete crystal, so far only one has been recovered. That one was a nearly perfect tabular specimen about 10cm X 6cm X 2cm, found in August by a geologist friend I had invited along to help scout the site. She now has that piece in her collection in Virginia. (I wouldn't turn loose of it either.) If you'd like to try to do some horse trading, I'm sure she would listen to any offers. Send me your e-mail address via the address I gave in an the previous message, and I'll put you two in touch with each other. In the meantime, I've found many partial crystals, but so far no complete ones. Don't lose hope though, the pegmatologists just want to document everything that's taken out of the pegmatite before it gets away. This way, they can make some sort of educated guess as to the quantity of material that can be expected to be taken from the site. This info is used to predict whether or not the site is of economic value as a mine.

Frank

Great finds Franklin! I've got to remember to send you the Dallas pyrites.

Pardon my ignorance, but I didn't think samarskite per se was radioactive. Is it a variety of samarskite (yes I read the postings about variety names!!!)that has radioactive elements as part of the structure?

I would be interested in trading for some Texas minerals, we don't see many up east. Even Terlingua Calcite is a bit rare. I saw a very small Dallas pyrite at a recent show but it was only a thumbnail (nothing against thumbnails, most of my specimens are this size!) and quite overpriced.

Just send me an email Jeremy, and I'll get you hooked up with some great pryites from here in Dallas. olmpiad@earthlink.net