I think this is one of three new colours released for Winter; I don't remember seeing it or Bronze Goddess (greenish bronze) or Goldmine (yellow gold) previously.
Sahara Treasure is a nice shimmery sandy beige, a slightly faded old gold shade. Goldmine is noticeably more yellow.
Swatches at different angles below. It's undeniably shimmery, but the colour is neutral and not so light that it's startling. I wore this to work today with some brown eyeliner without feeling too tinselly (although I do wear a lilac streak in my hair and rings with skulls on to work, so I'm probably not the most reliable suitable-for-work barometer.)
If you'd like to throw your hat in the ring for the spare Sahara Treasure, I want to know what your best present ever was. My decision is final (although if it's really hard I'll get Mr and Miss London to help). I'll close the competition and pick a winner on Sunday 04 December. You're welcome to enter by email or comment, but please either check back on my blog on 05 December or send me a contact email address to get hold of you if you win. Open internationally.