July 10

Shy Guy - Sometimes, when I go to see Mikey, he acts all shy. He is really a sweet guy. I frequently warn kids that he doesn't like all the shouting, screaming, and pounding on the viewing glass. A week ago, he got out of his pen right as the zoo was opening. Fortunately, or unfortunately, it wasn't my day to be there. Maybe he was looking for me, maybe be was after the kids.

Underworld Beach - I'm' back at it again. This was a virgin gypsum dam with little cave pearls in the dip below it. Cave pearls form when water dripping into the pool loses carbon dioxide and precipitates calcite. This precipitate usually forms around a nucleus of sand, bones, or fragments of soda straws or rafts. The typical roundness is due to the uniform growth of the pearl, not to any sort of rotation due to dripping. A sphere allows the greatest amount of deposition for the smallest surface area and is thus most likely, even if the nucleus is highly irregular. The dripping causes vibrations in the pool which may prevent the pearls from cementing (with calcite) to the pool floor, though many pearls are found cemented in. Sometimes excess precipitate will form cups or nests around the pearls, like in the photo on the top.