Finally I identified what I've got in my storage.It's zildjian, IIa stamp, almost 18" (17 7/8") cymbal.
What makes it outstanding from other is weight: 1090g! I've seen some pieces 300-400g heavier but never such a light one.
Unfortunately there is a small crack on bell, (1/9"-1/8"), slight keyhole and two tiny dents on the edge.
Sounds wonderful but it's not my type, I'm not jazz player.
You can check the sound here: http://snd.sc/NfEZNu
Wish to sell it...What price should I call for that cymbal?