Hi, thank you for the comments.
I have tested the metal for silver and it is silver - my MD shows numbers of silver as well, with fine gold plate outside, yellowish part which are not so clear to see but under the magnifier it is very clear - gold. The cup is obviously not formed from a sheet of metal - it is casted and mybe this is the reason it was broken.
When the parts are together it is easy to see that both sides the ornaments are worn equally in the same way as you can hold it with your fingers many years in the same place to drink something - as you will hold a rithon in the same place with your fingers. It means this cup was used for a long time as gold plate is worn and even the ornaments are well worn in oposite direction. It is not new cup for rithuals and tombs. Maybe the ornaments will tell us more as I could not figure out are they some cones or something else - some totem sign of the Thracians, Celts or Otoman? This cup is very old but here I can not test it how old is it. I can test only the metals in it.
Also in the inner part there is not traces of hammering of something and I don't thing it could be a bell. I found this cup quite near a small path in the Balkan, some 800 m high, the small river is bellow that place some 100 metters maybe it is a lost part of some treasure or broken by accident. The inner part is rough and clearly seen that it was casted. I don't think someone will ever make such casted bell of goldplated silver with these ornaments! Thank you again.