Question about burlington

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Does Burlington chert naturally occur with pink in it, or is that strictly from heat treatment? I have a piece that I believe to be an agate basin but it has some pink in it and it is making me question my typing of it. Everything other than the one little pink area seems right.

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Area in question

[willjo]

I think that could occur naturally, if it was near cortex some minerals may be responsible for the quality material and color, my thoughts others may have a better explanation.

[Broken Arrow]

That was a thought of mine as well. I also thought could have been incidental heat treatment through maybe a forest fire at some point.

[SurfaceHunter]

Looks like a field find the mineral deposits is the question? If so it looks like it might of come into contact with the farming equipment which causes the staining. I find it on cobblestones in the fields.

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No, the pink coloration is the question.

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Wondering about the frequency/possibility of pink coloration occurring naturally in Burlington.

[UpNorth]

Good question, I have a few pieces I’ve wondered about as well.

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I feel like I've read somewhere that it can occur naturally but I cant remember where.

[Artifascination]

Iron deposits can make a natural red/pink color tone in chert without heat.

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For sure. That was my thinking too.

[fldwlkr]

In their book "Prehistoric Chert Types of the Midwest", DeRegnaucourt and Georgiady state that Burlington is highly variable with colors ranging from white to tan, brown, cream, yellows, oranges, reds, pink, dark brown, and even black. Guess it could show bits of about any color.

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That is exactly where I read it but couldnt remember that source.

[Ron Kelley]

Hey Andrew, Burlington does sometimes have pink without being heat-treated. Also look at all the pink in keokuk which is a Burlington chert.

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That was my thinking too, just didnt want to lead anybody by posing the question with instances.

[Tam]

Andrew I always thought Burlington pink was from heat treating too . But if Ron says well that’s good enough for me .
I wonder about rocks cooling that’s always on my mind and how that does play into it .

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I had my own answer to the question, I was just wanting some reinforcement to it.