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I hope newbies are welcome to post New Topic...otherwise please ignore.Discovered this superb website today...(and spent all day reading!)Process? Rock Type?ThanksBeem
Quote from: beem on 02/02/2009 01:26:11I hope newbies are welcome to post New Topic...otherwise please ignore.Discovered this superb website today...(and spent all day reading!)Process? Rock Type?ThanksBeemDefinitely high-grade metamorphic rock- note the isoclinal/chevron folds. Probably a sheeted quartz vein before being so elegantly smashed and mashed. Gray looks like some sort of coating from weathering- or is it part of the rock? Is it metallic? (My guess is not, since it doesn't show any signs of oxidation).
Looks like erosion by water - my guess is that this is a thinly bedded sandstone/siltstone that has been rounded by stream erosion. Note how well rounded overall the rock is- the layers may contain thin laminations of mud or calcite that are more easily eroded, revealing the sedimentary layers.
Oh...oops [:I]Would it then follow that Rock #3's little square bit was at the top in the shallow streambed, because straight edges vs rounded evidence less erosion?All this talk about water (forgetting the glaciers for just a moment) is astounding, because the area now receives barely 13 inches rain annually.These rocks are all being labelled tomorrow. Thanks.Please let me know when you've had enough of this  Rock #4 Process? ID?Looks like it's been rusting inside?
Damn...I lost my Preview copy to timing out. Will learn procedure for Mohs hardness test this spring.Recently joined local rockhound club.The white covering on Rock #4 reminded me of a thin layer of hardened cracked cake icing, smooth and uniformly shiny, with no jagged pieces.Rock #5 Process? ID?Grateful you're still interested in looking! 
cored volcanic bomb
Oh, Oh, someone get Bass into his chains.! This is his favorite rock - a breccia. He will surely give the lecture on this specimen.
So #6 rock is a gneiss.And the red intrusions?low-grade garnet? or? [?]
Beem, you guessed right!! [:0]QuoteOh, Oh, someone get Bass into his chains.! This is his favorite rock - a breccia. He will surely give the lecture on this specimen.And since JimBob asked so nicely...Tectonic breccia- no doubt. Note that the clasts are all the same material, and that there is little rotation with matching boundaries.Solution collapse breccias typically contain a mix of clast types (but not always), and the clasts are obviously displaced- rotated, no matching clast boundaries, may be rounded, and are commonly coated with calcite rims or drusy calcite and/or quartz.There are two obvious fault structures cutting the rock, one from the upper right to the lower left, and another from the upper left to the middle where it gets cut off by the first fault.
Some educated guesses based on leaf shape are black cherry, beech, white birch, or ash; I would lean towards the last two. This site told me it could be a common pear: ...sorry, you cannot view external links. To see them, please
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Welcome to the inaugural meeting of the RHSAS (Rock Huggers Self-Appreciation Society) 
Rock #7, sorry for poor quality.Thanks!
Looks like you have a very nice gneiss on your hands.
how hard are the white and dark layers in this specimen, can you scratch them with a knife?