To clean or not to clean this piece of ancient glass

[Mark Z]

Hello Friends!

I just got this beautiful piece of ancient glass from FORVM.

Here's FORVM's listing:

https://www.forumancientcoins.com/catalog/roman-and-greek-coins.asp?param=32591q00.jpg&vpar=1636&zpg=38031&fld=https://www.forumancientcoins.com/Coins2/

I had a couple of questions for the experts related to cleaning this little gem:

1) Should I clean it at all? I haven't tried to remove any of the deposits but some of it has flaked off just from handling.

2) If I can and should clean it, how is that accomplished? DW soak like the coins?

There are some little adhesive tags with written numbers on it probably related to cataloging that I'm sure would fall off if it went into the soak. It might be nice if those could stay where they are just as an artifact of this piece's provenance. Take them off, clean and then replace them? (As a nice little extra, Mr. Malloy's original catalog tag was inside. I fished it out with tweezers!)

On the plus side, there seems to be some really pretty iridescence underneath the adhesions that you can't see too well that would look nice on display. 

Also on the plus side, despite having some cracks, this is a heavy piece that seems to be solid.

Clean it or leave it alone?

Thanks for your suggestions!

Regards,
mz

[quadrans]

Hi Mark,

Do not clean it please !

you loose the iridescence immediatelly and all of the antic feeling .

I do it one time and after I was very sad......


regards
quadrans

[Mark Z]

q,

Is the iridescence on the inside or outside, or is it within the fabric of the glass?

If it's on the inside, would I be able to soak it on the outside only?

Thanks!

mz

[Steve E]

Hi Mark,

The iridescence is alot like patina. A chemical reaction between the glass and the minerals in the soil. It can be on the inside or outside or both. Usually more so on the outside. Some "modern" glass collectors use vegetable oil to reduce the flaking of the scaley iridescence. I tried it once and am not totally convinced of the benefit

My, less than expert opinion, is to lightly rub the loose flakes off with a soft, dry cotton cloth, then leave it alone!

Like the patina of a coin, the iridescence shows it's ancient nature and authenticity IMO!

I think it is beautiful as it is!

~Steve

[Mark Z]

Steve,

I admit that I was still waffling but you tipped me in the direction of "do not touch."

I had flaked off a little of the outside stuff with my thumbnail as an experiment but between quadrans' and your advice, I think will leave it as is.

Thanks, my friend, and thanks to you, too, quadrans!

Regards,
mz

[Steve E]

You are most welcome!

~Steve