As a child, I remember combing the beach for interesting looking rocks. Some would look very non-descript - until I wet them in the ocean. The colors would then gleam and reveal interesting patterns.
The shores of the Antarctic peninsula were no exception. Though not as diverse as on New England beaches, there were still rocks with iron and potassium signatures and what I used to refer to as splotchy rocks, granitic rocks with inclusions.
This section of the painting required patience. In order to make it look like a rocky shore, I needed to take my time and employ lots of colors.