Feathery Crystals of the Park Point Ice Caves

What is the reason that these feathery ice crystals form? Tourists breathing and condensation?

I went to the Ice Caves Friday at mid-day. It was cool but too many people. I recommend, if you go and you'd better go soon, going early early early and on a weekday if you can swing. I'll bet it's nuts there this weekend.

Nice Jim! Glad you got this up. The crystal took a big hit after Wed.  Beauty is fleeting.  Now I need to figure out how and when to share my photos.  The caves here have been great and few saw them as it was so cold.  Nice to get together-maybe collaborate someday.