“We’ve looked at this, and there is no current evidence of any kind that shows any systematic use of tanzanite for terrorism,” says Mike O’Keefe, U.S. State Department desk officer for Madagascar and Tanzania. “Of course, we wouldn’t have any information if one person were trying to sell a stone here or there. But we always look for it.”

But others in the State Department have told the Washington Post and JCK that such a link cannot be completely disproved, and O’Keefe acknowledges that the tanzanite issue is not over. “The State Department always looks at any type of uncontrolled export. We’re working with the Tanzanian government in putting in place the Tucson Tanzanite Protocols,” he says. “And [in June], the government of Tanzania agreed to implement the certificate of origin [program] based on the Tucson protocols.”

O’Keefe hopes that uncontrolled exports will be completely eliminated. “The proposed certificate utilizes the language that Cecilia Gardner proposed,” he says. “And that’s a big step.” He adds that use of the certificate should make it a disadvantage to sell the gem “off on the side.”

But to control all exports, the mine area needs to be fenced off. “It’s roughly two square kilometers,” says O’Keefe. “Right now, AFGEM is pretty well fenced in.” That leaves three of the four blocks of the mine site left to be contained.

Other concerns include reports—unconfirmed—of children working in the mines. “There’s no evidence, and we saw none when we were there,” says O’Keefe. “On the whole, I think we’re making strong advances here.”