Granite Boulder

This boulder rolled and crashed and came to rest —
How long ago? — an isolate in the bush:
Pink orthoclase, black biotite, glassy quartz,
Coarse-grained from cooling underneath the earth.
Lichen began to spread in light-green patches,
And deeper green and a faded whiteish colour.
One face grew pitted like a honeycomb
Where wind and rain scooped the loose gravel out.
The base was cut in, leaving an overhang,
Shelter for spiderwebs and orchids. Rock,
Brute rock, a density of silence. A spinebill
Tracing its normal arc around the corner
Checks frantically at my immobile form,
Then darts off sideways through the scrub.