Pantone 459 color match. Tiny yellow Coquina shells.
My family and I went to Corpus Christi for a vacation the past few days. We had a great time, especially the kids. Made a few trips to the beach and found lots and lots of colorful tiny clams there.
The classic test to see if a mineral is calcium carbonate demonstrated - dropping a bit of dilute HCl on to a rock made of shells (a coquina) and watching it fizz as the acid reacts with the carbonate.