Rocks & Minerals B/C 2017

[Magikarpmaster629]

Identify:

1 (Click to Show Hidden Text)

[img]http://www.mindat.org/hpthumbs/HP_45292_800_602.jpg[/img]

2 (Click to Show Hidden Text)

[img]http://woodshole.er.usgs.gov/staffpages/boldale/pebbles/images/fig1_400.jpg[/img]

3 (Click to Show Hidden Text)

[img]http://www.mindat.org/hpthumbs/HP_180601_318_424.jpg[/img]

1. Chert?
2. Quartz var. milky
3. Quartz var. rose

[John Richardsim]

Identify:

1 (Click to Show Hidden Text)

[img]http://www.mindat.org/hpthumbs/HP_45292_800_602.jpg[/img]

2 (Click to Show Hidden Text)

[img]http://woodshole.er.usgs.gov/staffpages/boldale/pebbles/images/fig1_400.jpg[/img]

3 (Click to Show Hidden Text)

[img]http://www.mindat.org/hpthumbs/HP_180601_318_424.jpg[/img]

1. Chert?
2. Quartz var. milky
3. Quartz var. rose

Number 1 is opal. 2 and 3 are right. Your turn.

[Magikarpmaster629]

Really? Opal? Huh.

Just ID

[John Richardsim]

Breccia

[Magikarpmaster629]

Breccia

Wow that was fast. Yep!

[John Richardsim]

Identify and give crystal structure:

[Unome]

No one says "give crystal structure" unless it's... (Click to Show Hidden Text)

1. calcite 2. trigonal

[Magikarpmaster629]

No one says "give crystal structure" unless it's... (Click to Show Hidden Text)

1. calcite 2. trigonal

I think you need to start working on a binder or something...look at the cleavage; it's not at all like calcite

John, by crystal structure do you mean crystal system or crystal habit? I'll assume crystal system... 1. Gypsum 2. Monoclinic

[Unome]

No one says "give crystal structure" unless it's... (Click to Show Hidden Text)

1. calcite 2. trigonal

I think you need to start working on a binder or something...look at the cleavage; it's not at all like calcite

John, by crystal structure do you mean crystal system or crystal habit? I'll assume crystal system... 1. Gypsum 2. Monoclinic

Lol yeah I've done absolutely nothing for this event yet. I can ID exactly one mineral consistently (malachite).

[John Richardsim]

1. Gypsum 2. Monoclinic

Yes, but don't forget to include the variety (it's selenite). Your turn.