From just a quick look at your backlink profile, it looks a little spammy IMO. Lot of blogroll links and forum profiles on unrelated sites. Probably overoptimized for your keywords too.
You might try building out 30 web2.0's with unique content, 2-3 pages each, with some pics / videos on the pages and have them point to your site without using your keywords. Instead use stuff like click here, website, diamondrings.org, etc. as the anchor text. Throw in some links from authority sites as well on some of the pages.
Basically try watering down your anchor text optimization to make it look more natural and build higher quality links. (I have to do this too on my authority site that got hit from the Penguin update.)
You mentioned that you're getting 1000 visitors a month, where's your traffic coming from just out of curiosity? From the tool I'm using (ahrefs), it doesn't show your site higher than page 4 for any of your keywords.