Making paint and ink from wild sources is one of my passions (see Wild Color! Make Paint and Ink from Soil and Plants, in the Nature Journal Academy), and I couldn’t wait to get started in Alaska when we finally got back to our cabin in Fairbanks in June.

On a trip down the Richardson Highway to the Copper River, we stopped several times to gather pigment in the Alaska Range—at Rainbow Mountain (above) and at the stream that outflows from the Castner Glacier (below). The iron-rich soil and stones produced one of the richest reds (siennas) that I’ve ever worked with, and I was especially intrigued by the iridescent oxidation on some of the weather stones; the surface acts like a paint-stone—just by swiping a wet brush across, you get a beautiful reddish stain.

The pale silver soil I gathered next to Castner Creek is ground over many millennia courtesy the Castner Glacier. Over the millennia the glacier grinds its way slowly across the landscape, turning the underlying rhyolite, andesite, granite, and other intrusive igneous rocks (at depth) and sandstone and mudstone (closer to the surface) into what geologists call “glacial flour.”

Glacial flour comprises the lightest soil particles and they remain suspended in water, giving the region around glaciers the characteristic glowing turquoise and light blue, turquoise, or bright gray hues.

Castner Glacier particles are full of sparkly mica and the resulting paint maintains the metallic silver sheen. And yes those are porcupine tracks in the silt!

Sadly, the glacier, like most in Alaska, is melting much more rapidly now, and the sediment is increasing as more of the glacier releases its trapped soil.