Call for Posts!
Just a reminder - the October "Accretionary Wedge" is being hosted here at RAASP. We may be small, but we've cleared a whole blog entry just for this.
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Here's a preview:
Many geologists have access to a rock saw now and then. The desire to cut rocks into useful/interesting shapes can have quite a pull. I have no idea where the rock came from (save for the UW Geology Museum Giftshop, or exactly what it is - it's mass is 776.9 g. An estimate for volume put it at 283.1 cm3, which gives a specific gravity of about 2.74. It scratches glass, but not quartz.
I think it has some quartz mixed in, but I'm not sure about the green stuff. It kind of matches some of the descriptions of Scapolite group minerals, but the color seems a little weird a few flecks do fluoresce a pale yellow-white. It's got a generally metamorphic vibe/fabric, which is probably why it's causing me trouble. And yes, "vibe" should be a diagnostic category for rocks and minerals - we can put that into the next edition of Hurlbut & Klein.