# What Is This Green Rock/Mineral? **URL:** \ **Category:** Factual Questions\ **Created:** [November 11, 2013, 3:28pm UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649 "2013-11-11T15:28:44Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [November 11, 2013, 3:28pm UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/1 "2013-11-11T15:28:44Z")
I picked up some interesting rocks on a recent seashore visit. Just for fun, I put them in my daughter’s rock tumbler. Two turned out to be a bright apple green-with pink streaks. anybody know what mineral these are? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 11, 2013, 3:32pm UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/2 "2013-11-11T15:32:32Z")
Copper compounds are green. The most notable being Malachite. But, it’s more likely to be jadeite, which comes in both green and pink. ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [November 11, 2013, 3:37pm UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/3 "2013-11-11T15:37:25Z")
It would help to know where you were and if the rocks were loose on the beach or if they came from an outcrop. [Here’s](http://rocktumbler.com/polished-stones/) a tumbler ID too. ---
**Author:** ![Dendarii\_Dame](https://avatars.discourse-cdn.com/v4/letter/d/bbce88/32.png) [@Dendarii\_Dame](https://boards.straightdope.com/u/Dendarii_Dame)\ **Post date:** [November 11, 2013, 3:59pm UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/4 "2013-11-11T15:59:09Z")
[https://www.google.com/search?q=what+does+watermelon+tourmaline+look+like&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a](https://www.google.com/search?q=what+does+watermelon+tourmaline+look+like&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a) Could it be watermelon tourmaline? ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [November 11, 2013, 4:50pm UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/5 "2013-11-11T16:50:55Z")
Don’t show it to Superman. Trust me on this. 🙂 ---
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [November 11, 2013, 5:54pm UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/6 "2013-11-11T17:54:33Z")
> [@lieu](#): > > It would help to know where you were and if the rocks were loose on the beach or if they came from an outcrop. > > [Here’s](http://rocktumbler.com/polished-stones/) a tumbler ID too. Thanks…it looks like Unakite. the rocks were from the beach on Cape Cod (Sandwich, MA). ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [November 11, 2013, 6:17pm UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/7 "2013-11-11T18:17:32Z")
I figured orthoclase for the pink, it’s common and what you’d see for instance in some granites. A quick looks shows epidote in a lot of the gneiss and schist up there. Now the question becomes wherther it’s country rock or transported. While I have no experience in the area the history of glacial action means the till will contain a melange of rocks mixed and transported from a multitude of sources, some potentially hundreds of miles away. ---
**Author:** ![F.Pu-du-he-pa-as](https://avatars.discourse-cdn.com/v4/letter/f/c89c15/32.png) [@F.Pu-du-he-pa-as](https://boards.straightdope.com/u/F.Pu-du-he-pa-as)\ **Post date:** [November 12, 2013, 8:12pm UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/8 "2013-11-12T20:12:15Z")
Could you post a picture? I can’t identify a rock or mineral when I can’t at least see what it looks like. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [November 13, 2013, 11:33am UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/9 "2013-11-13T11:33:33Z")
Yes, pics. Apple-green screams epidote to me, but it’s hard to say without looking. ---
**Author:** ![the\_diego](https://avatars.discourse-cdn.com/v4/letter/t/7bcc69/32.png) [@the\_diego](https://boards.straightdope.com/u/the_diego)\ **Post date:** [November 15, 2013, 10:49am UTC](https://boards.straightdope.com/t/what-is-this-green-rock-mineral/673649/10 "2013-11-15T10:49:18Z")
Epidote, olivine, uvarovite, nephrite, or some alteration like chlorite. Pictures are needed.