1999-D Connecticut State Quarter With Silver Edge Question?

It has a D mintmark

Several companies produced "platinum" edition State Quarters...I vote plated...I dont think it is possible that the nickel layer was squeezed and flowed over the copper...but I have been wrong before...

The plated theory holds some water. Capitalizing on the uninformed, but highly enthusiastic public, hucksters plated coins in platinum, gold, silver, and even colorized these things. Some of these "collectibles" have been released into the wild as is the normal course of things as some people have already grown tired of holding onto these things, others find their way to dealers who inform the sellers that they have no value over face. When told of this, the sellers typically just get cash for change and the dealers spend them.

I'm sure a hundred or two hundred years for now these plated things and painted things will be a curiosity for 23rd century numismatists- unfortunately, we'll all be dead by then and won't get to hear what they think about the matter.

I just found one of these, 1999 d quarters. It is extremely brilliant. Not a proof. It weighs .1 grams more than clad quarters. It is plated with something. On very close inspection, you can see some plating imperfections on the reeded edges. The coin is more reflective than the mirror areas of proof coins. Platinum plated maybe?