Amber sea, garnet sand

Didn't find any Rangia cuneata today, but saw plenty of dark red sand on the beach today. It's not a rare, but a temporary phenomena: when the waves come at a certain speed at a certain angle, they drag the sand particles along the bottom, and the more heavy and dense grains are less prone to moving so they accumulate in some places and you get these bruise-colored patches of deposits. It's the same process as the one that was used to extract gold from sand in the past. Garnet happens to be quite dense, so it's one of the minerals that tends to accumulate in the fashion. Here's what it looks like:

I collected some samples and put them under magnification:

Turned out there were lots of grains of all sorts of colors. Pink and orange ones are garnets, I assume, and the occasional green ones - olivine. Colorless grains are ordinary quartz, but what could the really dark ones be? Maybe they came from basalt or something.

Publicado el junio 17, 2023 03:54 TARDE por tasty_y