LL land auctions -- why some USD, some L$?

Curious -- why are some LL land auctions in USD, and some in L$?

Complete sims seem to always be for USD. Smaller parcels seem to usually be for L$.

I thought that parcels would typically reflect abandoned land, but right now there are a whole bunch of parcels, all from 2 Sims (Whiskey and Steamboat), and to make me even more confused, all are L$ except for one which is in USD.

Just wondering if there was something I was missing.

That's a good question.. I was wondering the same thing myself.

Land auctions over 4096m2 are generally handled in US $

Land auctions 4096 and lower, are mostly auctioned in L$

The reason, at least as I was told, was to keep the sink for the L$. The theory was that anything over 4096 was be better handled with USD because this was done before the Lindex had arrived. I guess it also allows people that really don't ever want to use USD in SL can still get land from the auction in L$.

Thanks -- I see the method to the madness now