gone2china,
Yes indeed it must be nice... .
I suggest you run pairs. Check the literature (Schlitt, Rendu, Hartmann(ed.) come to mind).
For an international project, especially if you've got that nugget effect, run with labs on different continents as well as being with different firms. You may have to provide some significant backup down the road, courtesy of the Bre-X nonsense a few years back. Do a very good job of retaining splits or bulk 'pulps.'
The labs mentioned by ruble3 and jacare, and any in the professional mining & geology journals, will do just fine. Go the formal RFP route, checking qualifications and all. By the way, they, like everyone else, will knock the stuff down to run fire assays. Even if they go spectral(infrared), they'll still need to run some baselines with 'old-fashioned' fire assays.
If that's too much trouble, send them to me. I'll have time as soon as I finish re-reading Mark Twain and dismantling my thermostats. Honest.