Nice. It looks promising.
Please, take a look at crit dmg boss rings.
rol vs. ring of earth (critical damage)
http://imgur.com/a/RQ2jn
Should be at least +34 crit damage instead of +34
% crit damage imo

atm this ring is still useless (same with desert one).
You need to do tests with a full set of dmg jewelry... and please make concentration attribute useful.
<EDIT>
Finesse (Tricks) Target hit chance -10%