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View Full Version : Willow Creek Mining Dist. and Grass Valley Regin CA



Akson35
08-27-2012, 06:25 AM
hypothermal High Temp

Quartz lenses in shear zones 14ft thick

Principal sulphides are arsenopyrite pyrite

Snowbird and Snow King Mines history Ind. Mine and Reed Creek Little Su

3800 ft elv on up

Late Stage Quartz in Joint Planes
Fine Gold at .950
Mica Schist area more silver .750

I havent had luck with finding out more about Snowbird or Snow King mines and was hoping to see is anyone can help me with getting more reports of the area. I looked up land records about the Willow Creek Mining Dist but had no luck. Did a little digging around BLM but only have out dated reports. Looking for 2000 and up. With todays tec. I should be able to get some reports of the area if there is any.

1954 Ray: Thin AU Bering veins in sheere zone in tonalize: Finely Disseninated http://www.dggs.alaska.gov/webpubs/usgs/b/text/b0849c.PDF

I also was hoping to see if anyone on this site has any info about the Grass Valley Regin in CA.

Also if my findings are wrong please let me know. It is said to be four veins and I only have two of them:

North Vein N12 Dip 45
South Vein N 5 Dip 30

Thick quartz little gold, Thin quartz fine gold in lenses (Green Tint?) Elv ????

Bill Bohan
08-27-2012, 08:16 AM
MSpain or Lady frequents this forum. You might want to PM them as they own one of the larger load veins in the Willow Ck. District. Do you understand the geology of your posting?

Akson35
08-27-2012, 09:19 AM
Bill,

A little still having problems with what level I am at and finding reports that explain more about Sheers in the area. Also about green tint in tonalize what causes it to turn green?

Steve Herschbach
08-27-2012, 09:30 AM
You may want to keep it clear if you are talking about the Alaska location or the California location.

Akson35
08-27-2012, 09:37 AM
Sorry Steve,

Willow Creek Mining Dist. is compaired to the Mother Lode Grass Valley Regins of CA. in reguards to the type of vein if I read it right

Akson35
08-28-2012, 04:25 AM
http://ardf.wr.usgs.gov/ardf_data/Anchorage.pdf

http://www.dggs.alaska.gov/webpubs/outside/text/dnag_ch16.PDF

Geologic description:
Mineralized shear zones and quartz veins in tonalite or quartz diorite of the Late Cretaceous
Willow Creek Pluton. Exploration encountered four shear zones, two of which
contained gold in quartz lenses in gouge and sheared rock. The shear zones generally
strike northeast and dip 52 to 70 NW. Two shear zones were barren, one yielded a few
good assays, and one had encouraging assays (Ray, 1954). Wall-rock alteration within a
few inches of the veins is intense, but seldom extends more than 10 to 12 inches beyond
the quartz filling. Sericitization and carbonate alteration predominate, but there is some
pyritization and in the outer parts of the alteration zone chloritization is present (Ray,
1954).
The Willow Creek Pluton is a zoned pluton: the outer part consists of hornblende quartz
diorite and lesser hornblende tonalite; the core consists of hornblende-biotite granodiorite,
and lesser hornblende-biotite quartz monzodiorite and biotite quartz monzonite.

GoldenGoose is there any reports of this area Snowbird Snow King Sherry like the one near Ophir?

Reno Chris
08-28-2012, 09:39 PM
I dont know that a comparison to the mineralization at Grass Valley in CA will be valid.

Here is some info:
Geology: An elongated body of granodiorite is in the central portion of the district. This body is five miles long in a north-south direction and 1/2 to two miles wide. It is intrusive into older metamorphic rocks and itself is cut by various dike rocks. Immediately east and west of the intrusion arc dark greenstones classified as metadiabase and metadiabase porphyry (so-called "porphyrites"), and continuing to the northeast are amphibolite schist, serpentine, gabbro and diorite, and slate. Just north of the granodiorite and to the southwest are slates, phyllite, quartzite, and schist of the Calaveras Formation (Carboniferous to Permian). A number of intermediate to basic dikes are present also, as well as a few aplite and granite porphyry dikes. Overlying part of the district to the east and to the northwest are Tertiary gravels, in turn largely overlain by andesite.
Ore Deposits: This is the most heavily mineralized and richest gold district in the state with a very large number of productive veins in a relatively small area. The veins fall into two major groups: 1) those of the granodiorite-greenstone area, which have gentle dips, and 2) those of the serpentine-amphibolite area, with steep dips (see fig. 8). The veins of the granodiorite area are either in the granodiorite or in the adjacent greenstone, entering the granodiorite at depth. One group of veins strikes north and dips gently (about 35' on the average) either east or west. This group includes the Empire, Pennsylvania, Osborne Hill, Omaha, W.Y.O.D., and Allison Ranch veins. The other group of veins in the granodiorite strikes west or northwest and dips gently north. The North Star and New York Hill veins are included in this group. In the serpentine-amphibolite area the veins strike northwest and dip steeply southwest; a few dip northeast. These occur mostly in the amphibolite near or at the serpentine contact. The Idaho-Maryland, Brunswick, and Union Hill mines are here.
The veins usually range from one to 10 feet in thickness and consist of quartz with some calcite and ankerite. They fill minor thrust faults. Quartz is the principal vein material, and it appears in several textural types representative of successive stages of mineralization. Comb quartz, milky quartz, ribbon quartz, and brecciated quartz are the most common varieties. Many veins contain several generations of quartz. There are numerous northeast-striking, vertical or steeply-dipping fractures or "crossings" that commonly are boundaries of ore shoots. The' ore contains free sold and varying amounts of sulfides, chiefly pyrite. Present in smaller amounts are galena, chalcopyrite, arsenopyrite, sphalerite, and pyrrhotite. Gold occurs in cracks and grain boundaries in the sulfides and in brecciated quartz. Galena is commonly associated with the gold.
The ore shoots vary considerably in size and shape, and the distribution of gold within the shoots is erratic. Some have pitch lengths of up to several thousand feet, and the veins have been developed to inclined depths of as much as I 1,000 feet. Commonly bounding the ore shoots in the granodiorite are vertical or steeply dipping fractures, called crossings, that strike northeast, normal to the long axis of the granodiorite body. Much specimen ore has been found, but milling ore usually averaged from 0.25 to 0.5 ounce of gold per ton. Coarse-grained scheelite is present in several veins, notably in the Union Hill and New Brunswick mines.

Akson35
08-28-2012, 11:58 PM
Reno Chris,

Thanks for the info. I wanted to find out more methods whiched were used during the old days of mining quartz.

Reno Chris
08-29-2012, 06:10 PM
I've got a lot of that type of info on my website.

Chris

Akson35
08-31-2012, 04:22 AM
At or around mile 3 on the gold mint trail to the west is a quartz vein, anyone has looked at it?