There is a big difference between copal and amber. Bottom line copal resin that has not polymerised as much as regular amber and thus is slightly softer. This copal also has some other characteristics that distinguish it from amber.
Dominican copal is generally lighter colored. It is softer and the animals inside are slightly different. Some of the copal will soften in acetone, but much of the copal does not soften in alcohol as other copals often do. I am not familiar with the age of Dominican copal and can only state that it is younger than Dominican amber.
I do find that the preservation of the animals is slightly different than amber. I see a lot more air bubbles in copal. Many of the air bubbles can surround the animal. The color on the insects is often more pronounced and the color of the resin is slightly lighter than amber, it does not usually have that deep color that regular amber does.
We are the only web site in the world to sell Dominican copal with insects inside. If you do not have any of this in your collection, it is worth having some, just to be able to claim that you have Dominican copal (rather rare). So enjoy the page below, you will not see anything like this again.
By the way, we do sell bulk Dominican copal also - take a look near the bottom of the page.