In 0.9.4 silver ingot can be smelled to the same ingot, without getting exp from this
I think the problem in tags, because in 0.9.3 it doesn't work
Here is the screenshot from the REI btw

Hello!
Thank you for raising this issue! I have found the problem, and it is indeed related to the tags.
I renamed the files wrongly, meaning silver ores and silver ingots switched places.
I will fix this as soon as possible in an upcoming update. Thanks for posting the issue!

There is a problem with electrum [alloy] too. The it's texture (and recipe of electrum irl) is gold+silver, but recipe used in your mod is a gold+zinc.

(Oh, and a little question: can i translate MythicMetalls to russian lang..?)

Yeah, feel free to make a translation. Submit it as a pull request or upload the file as an issue, and i will include it