OK, no one is going to need this, I think, but I have skied (with a lot of difficulty)Saharan snow.
I kid you not. The snow was a kind of pinkish-yellow and unbelievably sticky -- you could hardly get any kind of flow going on less than a 30 degree slope. It was the end of the season and the snow was falling through a warmish atmosphere, but the explanation was that the clouds had formed over the Sahara and were bringing ultra-fine sand with them. Hence the colour and the stickiness.
As I'm writing this, I can't help wondering whether whoever told me this (a guide?) then went off to a bar and had drinks bought for him all evening because of how he fooled some incredibly stupid English people by telling them a tale about Saharan snow.
Perhaps it was really some kind of algae. But I can say that it really was there in Courmayeur and Chamonix as well as Val d'Isere over that week and that it was pretty much impossible to ski.
Do you ever get anything like it in the Rockies?