What you say is certainly true.

Apart from Baltic amber (that is, succinite from Northern Europe, that spans England to Russia, and Scandinavia to Germany), the primary sources of amber traditionally have been:

Sicily (Catanite)
Rumania (Rumanite)
China
Burma (Burmite)
The Dominican Republic (copal and amber)
Chiapas, México

These are places where amber of large enough quantities and sizes, and nice enough qualities, have been exploited. And some of these sources yield amber that has characteristics that are generally not found among Baltic amber sources. (The reverse is true as well.) Some of these sources, such as Rumania and Sicily have (apparently) not been commercially exploited in the mid-20th C. to the present—and we never see this stuff in the marketplace. For instance, I know people who go to Sicily who have never heard of any local amber. (It's a small place.)

In addition to the above minor sources, there are also less-significant sources of amber, such as Lebanon and Syria, Canada, New Jersey—and even California. (And quite a few more.) Amber is considered a rare material, though it can be found many places. And in many of those places it is so rare there is practically no exploitation of the material—especially no commercial exploitation.

If you were to take all the amber from minor sources and the most minimal sources, and put it all together, it would be a FRACTION of the amber produced from Baltic sources (primarily Latvia, Lithuania, Poland, and Germany (including the former Prussia).

Baltic amber is world famous for these reasons: It has been exploited for the longest length of time (at least since 10,000 BCE), has provided the largest quantity of material, the best quality, and has traveled nearly everywhere (in the "old" world particularly).

So, while it's well and fine to say there are many sources of amber, statistically speaking, one is definitely more likely to have a piece of Baltic amber than from any other source (if it is real amber, of course). f you go to México you're more likely to find Méxican amber there. Go to The Dominican Republic, and it's Dominican amber they will be offering. (Usually.) But I am mainly speaking about what is available to us in the marketplace. If someone comes to us from Burma or México (etc.), they may have that relevant material.

South America is NOT a source of amber, as far as anyone has proven. There are actual amber beads from pre-Columbian times, from Colombia. (I have some.) But these days (over about the past ten years or so), the material that is sold as "Colombian amber" is actually local copal. (I am inclined to believe the pre-Columbian amber may have been acquired by trade with either México or Hispaniola.) There is also no amber in Africa. In North America it is reasonably rare, and I can't say I've ever seen any artifacts made from it and sold to anyone. So, we have to admit that ALL of the continents are not really well-represented in the marketplace.

I've been collecting amber for nearly 40 years—yet I have few non-Baltic specimens. No Rumanite, Catanite, and not a lot of Burmite. I have some Chinese amber (but what is called that is just as likely to be Baltic amber that went to China—and the same can be true of Tibet and many other places). Of course, I have hundreds of fakes....

Take care.

Jamey