Hi, ajoblanca!

Finally I found the producing enterprize of your cups. It's Druzhkovka Porcelain Plant.
Address:
Pedagogicheskaya street 1
Druzhkovka
Donetsk region
Ukraine 84205

Also it has an internet site http://www.farfor.si.net.ua/, which is very poor because, as I know, DPP has been bankrupted several times for the last several years. You can see there it's logo: miners lamp.

BTW Donbass is from "DONetsk coal BASin."

Druzhkovka is a town of 64000 population http://en.wikipedia.org/wiki/Druzhkivka.