It is not possible.
We do not accept proposals for identify-this style sites. – animuson♦
Ok, so I went to Area51 and I posted a proposal to open a new site.
If we remember it, we received ~5 questions each day wich is more than Earth Science ratio (2.6 questions/day). This is enought traffic for a new site.
I think we could manage it better on a separate site with the guideliness we posted with effort.
Reasons to open a new site
There are a lot of users on the net searching to identify the minerals or rocks they find. The site would have yes or yes traffic. We received ~5 questions each day.
Reasons not to open a new site
It is sometimes difficult to identify the pieces and geologists may don't want to participate.