colour of ambergris varies from black, through dark brown,
through light brown to yellow/gold or even grey. The colour
tends to lighten with time.
Most frequently, good quality ambergris is a dark to light
Sometimes, a grey/white, powdery crystallisation is formed
on the surface.....often in uneven patches.
texture is granulous. The "kidneys" have a tighter
and finer texture than the layers or strata.
are some pictures: