I found this tiny "pebble" lying at a beach north of Chicago when hunting for interesting non-fossil beach rocks and sea glass. (Yeah, there are people who collect and love sea glass and "just rocks" :-)
So now, that I've started to collect coral fossils as well, mostly corals, I've been taking a closer look at some of my old finds and see all sorts of little fossil bits and pieces. This one when I found it, had caught my attention due to the tiny pattern, which I thought at the time was maybe something man-made. (Near a big city, there is a lot of man-made tumbled material to be found at the beaches). Looking at it with my magnifying glass, I saw that the individual white spots seem to have the same starlike pattern as the large corals I find. But this thing is almost microscopic.
Is/was there really coral with such tiny corallites? If yes, what is its name? Maybe a tiny favositid?
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