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Hardstone Cameo Staining
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Author:  Frederick [ Mon Feb 18, 2019 5:17 am ]
Post subject:  Hardstone Cameo Staining

A small Cameo came into my hands in last month. I noticed the back ground, which was brown had a chip in. The chip showed a diffrent colour from the surrounding back ground material .It was small and I did not think any more about it .
Last week larger cameo came in to my hands from the same source, it had several larger chips on the back ground which were more obvious .It appears the whole cameo is not cut from a layered agate or layered stone but it is cut out of the same white material and the back ground has been stained brown. The staining is not surface paint but is a staining treatment.
The stone is in a prity mount with a millgrain setting, it has not been set but stuck with resin glue .
My question is is this a new piece in an old mount or have cameos always been treated in this way and I have just not come across this problem before.
I look forward to any comments .

Author:  Stephen Challener [ Mon Feb 18, 2019 5:23 pm ]
Post subject:  Re: Hardstone Cameo Staining

Dying of some sort or other in cameos is an ancient practice, going back to the classical era at least. Naturally banded materials with appropriate coloration do exist in nature but they're a lot harder to reliably source than common grey agate (like those produced from Brazil) which can be easily dyed due to differential porosity between bands. Some dyed agates do only show color on the surface, though I am not sure if that would be typical for material that had been cut as a cameo.

Author:  Isi [ Mon Feb 18, 2019 5:49 pm ]
Post subject:  Re: Hardstone Cameo Staining

Could you please show pictures of these cameos you are talking about and their chips and layers ?

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