Chocolate Glass?

Do we have any experts on chocolate glass? If so, how can you tell antique chocolate glass from reproduction (if there are reproductions)? I bought this piece a few years ago and often wondered if it was old.

 

looks like it may be original to me; RoR has an article about these. Repros were made by Kemple and Summit

https://www.realorrepro.com/article/Greentown-dolphin

might also compare to examples here:

http://www.eapgs.org/patterns/full-images.php?idx=52252&pat=2157

 

Thanks everyone. The first link was really helpful and encouraging. I did not know there was a "beaded" rim and "sawtooth" rim. Judging from the size of the eye in comparison to the body, the shape of the fin as it intersects with the body and at the end of the fin, and the fish finial's head shape, it does appear to be an original "sawtooth" rim piece.

 

THAT LINK was SO INFORMATIVE!!!!!!!!!!!!!!!!!!!! AND LOVE this Fish Dish!!!!

 

Compared to the link TallCakes posted the tail piece shown is not original. Straight not saw tooth?

 

The straight tail is on the reproduction "beaded" version of this piece. See the tail design on the "sawtooth" version. Both the reproduction and original of the "sawtooth" version are nearly the same tail. See Figure 10 and Figure 11.

Another thing I noticed that I had not realized, this is a larger fish coming up to eat a smaller fish. That is so cool.

 

I had that wrong. I should have said the straight tail is on the original "beaded" version of this piece. The "serrated-style" tail is on the reproduction "beaded" version, the reproduction "sawtooth" version, and original "sawtooth" version. I apologize if I confused anyone.