It's fun to guess what it was before knowing the scale - it looks milky initially.

I wonder what the rock is. One of my favorite facts is that the white surface of the moon is feldspar, which rides "frozen like icebergs" on a sea of basalt. The darker mares are where the basalt has risen to the surface.

This crater looks almost like porcelain
http://www.stevetobin.com/explodedclay/clay3.html

Absolutely beautiful. Please forgive my ignorance if I ask to know more about it.

Omega, yes I think it's milky looking too - it's hard to tell what it is.

Bill, maybe you can find out what rock that is. Thanks for the link- I particularly like the left image, rather like this one I featured here! Good choice.

Daniel - yes, isn't it! Did you check out the link Victoria? Sorry if it didn't stand out very much... Thanks for dropping by.

Ooooh. I like that.