# Iridescence Question



## AuSmith (Oct 31, 2012)

When I did anthropological fieldwork we dug a 17th century wine cellar- we found  plenty of thick pointilated  bottles,and bottoms of bottles  (some black glass). We never removed the iridescence from them .I have recently found a  large cache  of  very very old bottles some of which are heavily iridescent- are they more salable clean or in the condition as found- minus  any  interior residues or dirt, or in  one case tincture of  opium( on a bottle that is corked  but contents highly concentrated from evaporation)?
  If I should get a consensus that says to clean 'em, what is the best way to remove the  iridescence without abrading the glass, other than tumbling which I am  not going to do.
 Thanks


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## surfaceone (Oct 31, 2012)

> I have recently found a large cache of very very old bottles some of which are heavily iridescent- are they more salable clean or in the condition as found- minus any interior residues or dirt, or in one case tincture of opium( on a bottle that is corked but contents highly concentrated from evaporation)?


 
 Hello there,

 Welcome to this place. It's impossible to advise you without good photos of the bottles to which you refer. One person's stain is another's Benicia effect.

 Personally, I'm very fond of wild iridescence, copious opalescence and the like. Extra points for pointilated, too. [8D]


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## chosi (Oct 31, 2012)

I don't think there's any sure way to remove iridescense without tumbling or using dangerous acids.  There are various cleaning methods that will remove "most" of the iridescense, but what you'll be left with is a bottle with cloudy glass, which in my opinion looks less attractive than the iridescense.


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## Plumbata (Nov 1, 2012)

Assuming that the iridescence is visually appealing, the items will likely fetch a premium. Some iridescent bottles with truly superb iridescence, even if 5 or 10 dollar bottles normally, will fetch a very significant premium. Personally, I love the effect and consider them to be quite a bit more valuable than an identical bottle without the thin layer of opalescent film. Some may disagree and consider them damaged or "sick", but the fair open market prices seem to demonstrate otherwise.


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