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12-29-2010, 10:22 PM
Theres a lot of talk these days about the importance of Rare Earth elements in our world. With China cutting its exports, its 97% market share and ever increasing demand worldwide, this is very significant.

U.S. at risk of rare earths supply disruptionsU.S. at risk of rare earths supply disruptions (http://www.reuters.com/article/idUSTRE6BE1D320101215)

Rare earth element From Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Rare_earths)

Rare earths shares jump after China quota cut (http://news.yahoo.com/s/nm/20101229/tc_nm/us_china_rareearth_8)

I was doing my usual browsing of the web/GE for dredge related information and came across some history. First I found the remains this dredge, located near Leland, Oregon on Grave Creek.


With the dredging finished, it was moved to Cascade Idaho.


One of the minerals collected during dredging, besides gold is monazite, which contains several rare earth metals.

Monazite From Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Monazite)

Besides this dredge, three additional bucketline dredges operated on Bear Valley Creek, dredging exclusively for Monazite in the early '50's.




- "An entirely different kind of dredging production came to Long Valley several decades later. When the principal sources for imported monazite were cut off in 1946 to 1950, an examination of Idaho possibilities for replacement led to extensive Long Valley dredging for monazite beginning in January of 1951. Three dredges operated that year. One capsized and sank in 1953, and lack of a market led to suspension of both remaining dredges in 1955. By that time, monazite production had reached about two-million dollars. By-products raised total production value there to $3,500,000 when mining ceased.

The Principal Rare Earth Elements Deposits of the United States (http://pubs.usgs.gov/sir/2010/5220/downloads/SIR10-5220.pdf)

"In the 1950s, two areas of west-central Idaho were mined by dredges for monazite, Long Valley and Bear Valley. Beginning in September 1950, Long Valley was worked by three dredges that had earlier been used to recover gold but later were converted (with assistance from the U.S. Bureau of Mines under the sponsorship of the U.S. Atomic Energy Commission) to recover monazite. The history of these dredging operations is described by Argall (1954) and Staatz and others (1980, p. 9–16, and references cited therein). During this 5-year period, Staatz and others (1980) estimated that the three dredges recovered 6,430 metric tons (7,085 tons) of monazite containing 269 metric tons (297 tons) of thorium oxide. Dredging ended here in mid-1955, when the government stockpile order was fulfilled. The Bear Valley placers were worked by first one dredge in 1955, then a second in 1956, with the intent to recover Nb and Ta for another Federal government contract. According to Staatz and others (1980, p. 10), “from alluvium of Bear Valley, 2,049 short tons [1,858 metric tons] of euxenite, 83.5 tons [75.7 metric tons] of columbite, and 54,862 tons [49,760 metric tons] of ilmenite were recovered.” No records of monazite recovery were kept."
-cited above-


Figure 20. Porter Brothers dredge in Bear Valley, Idaho, worked columbium (now called niobium)-tantalum placer deposits. This dredge operated from 1955 to 1960; exact date of photograph is unknown. Monazite was produced as a byproduct from these placer deposits. (Photograph from Savage (1961, fig. 13); used with permission of Idaho Geological Survey.)

"At one locality in upper Bear Valley in the late 1950s, placers that contained euxenite as the predominant radioactive mineral were mined for uranium, rare earths, and associated heavy-mineral products. The mining operations consisted of dredging and jigging the raw placer material to wash and mechanically separate out the valued heavy-mineral black-sand fraction. About 8,500 cubic yards of stream gravels per day were recovered using two dredges. The amount of black-sand concentrate recovered per cubic yard of dredged raw gravel ranged between 45 to 140 pounds. The black-sand jig concentrate was transported to the Lowman mill site for further upgrading."

Lowman Mill and Disposal Site Boise County, Idaho (http://www.eia.doe.gov/cneaf/nuclear/page/umtra/lowman_title1.html)

Southern Idaho ghost towns By Wayne C. Sparling (http://books.google.com/books?id=Oyet3Zdhj-4C&pg=PA128&lpg=PA128&dq=bear+valley+monazite+dredging&source=bl&ots=0M8OTzXk-L&sig=n0Ee_UGsNGnSr2RkytAgGaSlpFk&hl=en&ei=u8sbTc7sGYumsQOby6SmCg&sa=X&oi=book_result&ct=result&resnum=9&ved=0CDIQ6AEwCA#v=onepage&q&f=false)



The monazite dredges suspended operations when purchases by the Atomic Energy Commission ceased, the only market for the recovered material (Murray, 1999, Cook, 1957). (http://www.idwr.idaho.gov/waterboard/WaterPlanning/CompBasinPlanning/Payette/PDF/Payette%20Resource%20Values.pdf)

In the Big Creek area near Cascade, Idaho, Baumhoff-Marshall, Inc., and Idaho-Canadian Dredging Co., both of Boise, Idaho, maintained equipment for dredging monazite sands. Their operations were curtailed in mid-1955, however, owing to competition from imported ores. (http://digicoll.library.wisc.edu/cgi-bin/EcoNatRes/EcoNatRes-idx?type=turn&id=EcoNatRes.MinYB1956v1&entity=EcoNatRes.MinYB1956v1.p1164&isize=text)

The Wall Street Journal, lIaroh 20, 1'52, oontains an article on rare earth minerals which are being extracted rrom the Idaho sand depOSits in Warran Valley about 60 miles
north ot Boise. the monazite sands are extraoted by three dredges owned by Baumhort-Karshall Company, Warren Dredging Company, and Idaho Canadian Dredging Company. the heavy Bands ara oono'entrated on the dredges and are then truoked to a separating plant at Boi.e. In this plant elactromagnatic machines are used. BeSides monazite, whioh is the real inoentive for mining the sands, magnetite, ilmenite, garnet, and zircon are recovered. At present thase
by-products have little or no market,.but are potentially valuable. lIost ot the Idaho output goes to the Lindsay Light and Chemical Company, Chicago. Shipments to this company are at the rat. of about 1500 tons yearly and it is expeoted that additional dredges will be put into operation and that in another year the amount to be treated by the tirm will be three t1me. as much as at present. Rare Earth, Inc., Patterson, New Jers,y. is another consumer
or the monazite."


Steve Herschbach
12-29-2010, 10:30 PM
Great post. The fact is rare earths are not rare. The only reason China is about the sole source is they have no environmental standards. They mine in ways we would never allow here. But if we need rare earths there are plenty of US sources. Some here in Alaska.

12-29-2010, 10:36 PM
But if we need rare earths there are plenty of US sources. Some here in Alaska.

Rare earth elements: Alaska’s resource future? (http://www.alaskadispatch.com/dispatches/economy/8048-rare-earth-elements-alaskas-resource-future)

US Team Studies Alaskan Rare Earth Deposit (http://www.resourceinvestor.com/News/2010/9/Pages/US-Team-Sudies-Alaskan-Rare-Earth-Deposit.aspx)

These are both good reads.

Rare earths are a bright spot for Alaska's future (http://www.adn.com/2010/11/06/1540509/rare-earths-are-a-bright-spot.html)

Reno Chris
12-30-2010, 12:56 PM
For any of you that subscribe to the ICMJ, I did a feature article on Molycorp and rare earths in Nov. of 2009.

The worst of the Chinese rare earth mines is not so much in the mining itself, but the processing of the ore which generates large amounts of spent acids that the Chinese dump in local rivers or pour into pond areas so the acid can sink down into the ground water table.

Geo Jim
12-30-2010, 10:37 PM
Thanks for the info on rare earths in the lower 48. I may have to prospect for them too. Good thread.
Geo Jim

01-01-2011, 03:35 PM
From what I can tell, the trouble with the rare earths is not finding them, we know where there are plenty; it is that the refining process is so darned difficult that the easy part is finding and mining the ore. The refining plants take several years to get designed and built, and right now China has most of them. There are only a few non-China outfits with refineries, one being Great Western Minerals, which goes from "mine to magnets", but which has low capacity right now. Another is Lynas Corp, an aussie outfit with a deposit high in the heavy rare earths that are more desirable and expensive, PLUS a plant that is coming online in 2011 in Malaysia to process and refine the ore.
Molycorp's deposit in California is low in heavy REs but they do have the capacity to refine the light REs they mine, which makes them a popular outfit.
And the biggest problem with the Chinese sources is that even the government admits that HALF of the supply of REs coming from China is coming from illegal criminal gang-run mines. Which means that HALF of the global supply of rare earths is coming from these criminals. You can imagine their concept of reclamation and safe practices.....
But all the rest of the hundred or so RE prospects are many years away from producing finished RE metals for industrial consumption. I read recently that Rare Earth Elements, stock ticker REE, just for one example, had two or three employees and a few boxes of papers documenting their claims in Wyoming, and that is it. They are 7 to 9 years away from selling refined rare earths. Yet their company has a net worth of $560,000,000.00!
So there is an interesting phenomenon goping on; a bubble of ignorant investors rushing around from company to company inflating stock prices dramatically; and the very real shortage of REs now upon us, which will only be made much worse if China takes the necessary steps to halt the illegal mining operations. But by the time these prospect-level mines are on line, there will be no more shortage of AREs and their price will have dropped. Ought to be an interesting train wreck.
Another possible joker in the pot is the "strategic mineral" concept; I believe there is currently a bill in the Senate to use government dollars to support the creation of more US sources of REs. Oink, oink, a real political pork barrel feast that'll be, ans it is what investors in REE, Molycorp, etc are hoping for.
I am taking the approach of onloy investing in companies which will be producing REs, especially heavy REs, within the next couple of years; I think when the dust settles and investors become better educated the prospect companies will fall by the wayside pretty quickly.
Could be wrong of course, I have been so before!
And yep i have positions in Great Western Minerals and Lynas Corp.