Andean Opal

Hi there,
I would love to buy some Andean opal. However, I keep reading about how rare it is and how it is sometimes dyed etc…
I have found some beautiful looking blue green stones, I am very close to buying but am worrying that it might not be the real thing. The dealer has said the mines have closed now. There are no certificates of authenticity.

Here is a pic…
Any tips for me about what to look for? Does it look genuine
How to distinguish between chrysoprase and Andean Opal for example? This might sound very silly so please excuse my ignorance.
I just want to make sure that before I part with my wages I have a chance of getting it right.
Thanks very much for your help.
Laura B

So, I am not even close to an expert, I don’t even have a good mineral collection yet… But, when I hear opal I think opalescent. The stone in the picture doesn’t look like it is at all. I have seen a few opal that just have veins or like crackles of opalescence in them. But, even if it’s pretty solid looking… There is something. They can be needle point big and spread far apart throughout…But it’s there if it’s there. And, it shows in pics. If someone told me this was an opal and told me they have absolutely no proof of that. I wouldn’t believe them. That’s just me though.

Looks like good quality Andean Opal to me… Andean Opal has no so-called opalescence @ all… more like blue green glass…