ericabelle
spending too much on rocks
Instagram acct: @erica_shoots_everything
Member since April 2021
Posts: 482
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Post by ericabelle on Sept 1, 2022 15:29:28 GMT -5
Well, I've got a mild case of COVID, so I decided to go rockhounding in the wooded lot across the road yesterday. (My version of taking it easy.) I always find weird rocks there, and it had just been brush hogged so I knew that the ground would be torn up a little, exposing new rocks. I find interesting chalcedony there, sometimes pink, yellow, or peachy orange and it often has a random white coating over parts of it. This piece I found yesterday actually had a pattern in the white coating. And if you look closely, you can see some round white orbs in the chalcedony! Does anyone know what the white coating is? And how did it achieve this pattern on this rock?  |
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ericabelle
spending too much on rocks
Instagram acct: @erica_shoots_everything
Member since April 2021
Posts: 482
|
Post by ericabelle on Sept 1, 2022 19:04:09 GMT -5
So I found this snippet on an Earth Science website where someone posted a similar question. Someone answered and suggested it was opalization. I have to say most of their photos look like the white coating is pretty deep - sometimes it is on my rocks, too. Sometimes it tumbles out, sometimes it doesn't. The third photo they post of the orange chalcedony is the color that I love to find. I think it is so unusual, but maybe just unusual for this area (SE Missouri) Here is the website: earthscience.stackexchange.com/questions/9589/what-is-the-white-coating-patina-we-often-see-on-deposited-chalcedony-agate |
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Post by vegasjames on Sept 1, 2022 21:42:55 GMT -5
It is silica, but from I have found most of it is white chalcedony. It is as hard as the chalcedonies I commonly find it on. Chalcedonies do start out as opals though.
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Post by vegasjames on Sept 1, 2022 21:48:35 GMT -5
So I found this snippet on an Earth Science website where someone posted a similar question. Someone answered and suggested it was opalization. I have to say most of their photos look like the white coating is pretty deep - sometimes it is on my rocks, too. Sometimes it tumbles out, sometimes it doesn't. The third photo they post of the orange chalcedony is the color that I love to find. I think it is so unusual, but maybe just unusual for this area (SE Missouri) Here is the website: earthscience.stackexchange.com/questions/9589/what-is-the-white-coating-patina-we-often-see-on-deposited-chalcedony-agateI used to know where there was a lot of orange chalcedony here in Southern Nevada. The main deposit was at a mine that also had a lot of purple chalcedony. I took a group of people on a trip and sowed them several locations including this one, which is in the middle of nowhere and not easy to find. I cam back a month later and all the orange chalcedony and most the purple chalcedony had been removed. I am sure it was someone that was on the trip.
A lot of people on the rock boards complain when others will not share their spots, but this is a great example of why.
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Post by vegasjames on Sept 1, 2022 21:55:38 GMT -5
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Post by rmf on Sept 2, 2022 3:10:06 GMT -5
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Post by fernwood on Sept 2, 2022 3:50:31 GMT -5
I agree on the coral ID.
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ericabelle
spending too much on rocks
Instagram acct: @erica_shoots_everything
Member since April 2021
Posts: 482
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Post by ericabelle on Sept 2, 2022 5:51:54 GMT -5
It is silica, but from I have found most of it is white chalcedony. It is as hard as the chalcedonies I commonly find it on. Chalcedonies do start out as opals though. Thanks for the info and also the clarification on opals. For a while, I thought this material might be common opal, but I scratch tested it and found it was harder than opal. That is beautiful orange chalcedony! Just the color I find sometimes. The only drawback is, when it is lightened by other minerals, it is a really weird fleshy color. That is too bad about your chalcedony honey hole that someone took advantage of. I have the "advantage" of living in an area where there is nothing very sought after, but I still find rocks I get excited about. LOL |
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ericabelle
spending too much on rocks
Instagram acct: @erica_shoots_everything
Member since April 2021
Posts: 482
|
Post by ericabelle on Sept 2, 2022 6:03:08 GMT -5
That's so neat rmf and fernwood - I guess I won't be throwing that one into the tumbler! It's quite a coincidence, too, because I found this rock below nearby on the same day. I'm excited about it because I've never found a coral fossil here that looks so much like coral. The only places I've found fossils like this (but better) are in Oregon and Wisconsin. It has no pattern on the sides, just a reddish brown quartzite.   |
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Post by fernwood on Sept 2, 2022 6:07:13 GMT -5
That one looks like a favosite, honeycomb coral.
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