Andrew Trundlewagon's photos with the keyword: rock

Two forms of chalcedony; the top rock is mammillated chalcedony I found on a building site in Aylesbury in the UK. The white patina on the core is intriguing as it changes colour with the weather. When it is humid it becomes bluer, but it is white when the weather is dry. I have not been able to learn the chemistry behind this. The lower stone is banded agate, which is also a kind of chalcedony and which I bought in Sao Paulo, Brazil.

A green frog (Lithobates clamitans or Rana clamitans) on a rock beside a pool. It looks almost as though its head was dipped in a can of green paint. I was going to call it Prince Charming, but perhaps it's Princess Charming? Which led me to realize that I have no idea how to tell the females from the males by sight. A quick trip to Wikipedia revealed that in Green Frogs "the male tympanum is twice the diameter of the eye, whereas in females, the tympanum diameter is about the same as that of the eye, and males have bright yellow throats". So, this, it seems, is Princess Charming.

The same heron as in the previous photo, taken as the sun was starting to go down.

Part of a small swarm of bees that had settled at the base of a rock.

The inconspicuous flowers of Micranthes virginiensis, the early saxifrage or the Virgina saxifrage. This is an early spring wildflower that grows on rocks. The stems are long and leafless. A small rosette of dark green leaves hugs the rock surface. (Parc St. Bruno, Quebec, near Montreal). It is thought that the long stems prevent the pollen being taken by beetles and favours productive pollination by bees and other flying insects.

Chipmunk - with the snow slowly melting it has probably just recently emerged from hibernation.

A slightly tentative Chipmunk, not sure if it is safe to come out or not - with the snow slowly melting it has probably just recently emerged from hibernation.

A part of Percé rock, a landmark in the Gaspé peninsula, Quebec.

A small piece of polished Brazilian agate, photographed with a cell phone and magnifying lens. Curves and circles, a fractal-like swirls frozen in stone.