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hoarder
11-12-2011, 10:48 PM
I've been having some dirt work done on some property I have in Western Montana and the dozer operator said "Looky what I found" and showed me a glittery black piece of soft rock and said he thought it was galena. I'll post a picture of it tomorrow when I brave the cold to fetch my camera out of my truck. I looked up galena images on the net and confirmed it looks like galena.

What is the significance of finding galena? Does it mean lead or gold may be near?
I haven't figured out who owns the minerals to my property, it seems the person who owned them decades ago died and it was never probated.

gringott
11-13-2011, 05:05 AM
Galena is a common and popular mineral for rock hounds. Its characteristic cubes, distinctive cleavage and high density make it easy to identify and a favorite in high school geology labs. The structure of Galena is identical to that of halite, NaCl. The two minerals have the same crystal shapes, symmetry and cleavage. Some Galena may contain up to 1% silver in place of lead. The large volume of Galena that is processed for lead produces enough Silver as a by product to make Galena the leading ore of Silver.
To quote Allen N Wollscheidt,

"Galena, back 75 years ago, was the stuff -- the crystal -- of crystal radio sets. Surely you have heard of these -- possibly your grand or greatgrandparents built radio receivers out of round Quaker Oats boxes, a few feet of copper wire, a pair of headphones and a little "cats-whisker-with crystal" gadget from the hardware store. Some worked so well, they could be heard across the room.
Galena is a natural semiconductor and so the forerunner, the enabler, of all the electronic gadgets we have today, from telephones to TVs to GPS navigating systems as well as all sorts of medical equipment -- in short, modern life as we know it.”

PHYSICAL CHARACTERISTICS:


•Color is lead to silver gray sometimes with a bluish tint.
•Luster is metallic to dull in weathered faces.
•Transparency crystals are opaque.
•Crystal System is isometric; 4/m bar 3 2/m
•Crystal Habits include the cube, octahedron and combinations of the two. Spinel twinning is possible forming flattened crystals. Also massive and granular.
•Cleavage is perfect in four direction forming cubes.
•Fracture is uneven and rarely seen because of the perfect cleavage.
•Hardness is 2.5+
•Specific Gravity is approximately 7.5+ (heavy even for metallic minerals)
•Streak is lead gray
•Associated Minerals are calcite, dolomite, sphalerite, pyrite and other sulfide minerals, also lead oxidation minerals such as cerussite and anglesite.
•Other Characteristics: brighter metallic luster on cleavage surfaces than on crystal faces.
•Notable Occurances include Texas-Oklahoma-Missouri area, USA; Germany, Peru, Mexico, Zambia, and England.
•Best Field Indicators are crystal habit, cleavage and, perhaps most importantly, density.

hoarder
11-14-2011, 10:41 AM
Here is the pic of what might be galena:

gringott
11-14-2011, 06:00 PM
That kind of looks like the description, but I am not a geologist. I googled images and found this one that looks something like your picture, what do you think?

hoarder
11-14-2011, 06:05 PM
Mine doesn't have those squared features. When I looked for galena pics on the net I found the description to be rather broad.
http://www.bing.com/images/search?q=galena+images&qpvt=galena+images&FORM=IGRE

Argentium
11-14-2011, 08:42 PM
Galena can be deposited in either a massive (as in the photos), or in a crystalline form. Best ID would be density (specific gravity), or a streak test.

Goldhedge
11-14-2011, 09:29 PM
Is that a D9?

hoarder
11-14-2011, 09:39 PM
Is that a D9?That's a D8 from out of the 70's. It's one of the "46A tractor" series, which were the best.
It grunts along at 1800 RPM. Damn things last forever. Burns about $320 worth of diesel a day. It weighs 128,000 pounds.

The D8's and D6's of that era stand out ahead of all the rest.