Old Eisenberg Original Mexico Silver brooch stone identification

[ivcmom75]

Estate find and I need help with stone identification. Operculum, Green Onyx, Green Calcite??  Dating this 1930’s, do you agree? Vintage jewelry isn’t my specialty. Thanks all, Sue

[scifidaughter64]

Can't help on the stones. However, according to the Illusions Jewelry site that signature and the sterling jewerly was made between 43 and early 48.

[dream*peddler]

Very cool brooch!  I want to say Operculum, although the "eyes" are not very well defined.  Since it is an organic material, it could have been exposed to certain environmental conditions.  Also, there are a couple different color variations  for Operculum depending on the snail.   I love Operculum jewelry, but I love anything unusual .

[vernon1959]

very cool piece!

[flipping_treasures]

Neat brooch.  If I were buying this piece, I would have a problem with this signature.  The reason I say that is that the etching on the signature is over the patina on the brooch.  If this signature was etched at the time that the brooch was made, the patina should be over the signature, like it is on the Mexico on this brooch.  

[dream*peddler]

I think I see some crazing on a few of the cabs.  Unfortunately, that hurts the value of the piece.  Still a very interesting find!

[ms.sellainy]

Something bothered me about the mark but I couldn't define what it was. A light switched on when I read your astute observation, Sandy. I don't think it's ever occurred to me to notice, but I will henceforth because it makes sense. That's very keen sleuthing from where I sit. Thanks.

[ivcmom75]

I did rub the signature with my finger to I could read it better with my loop. I do know it has been buried in a box for over 30 or more years.

[ms.sellainy]

Forgot to say, I think it's a great design and construction looks equally good. The question I have is why would anyone feel a need to etch a name on something like this that has plenty of merit on its own? Apparently, a new looking etched mark could even hinder a sale if buyers notice the contrast in patina. I would certainly research an etched Eisenberg mark. 

[hollyblue83]

The stones may be Mexican onyx/travertine, they do not appear to be Operculum with the direction of the cracks.