1.35" Harpes Trilobite - Jorf, Morocco

Trilobites are collected from a 15-meter-thick section about 6kilometers northwest of Jorf, Morocco. Unlike many other localities, these rocks do not have distinct deposition layers, but rather are massive. They likely represent a gigantic "mud mound" that formed at the base of a volcanic island due to mud slides. The rock is very silicified, almost like a chert, and can be quite colorful. The actual shells on the trilobites are translucent: the trilobite tends to be the color of the rock it sits on.

Because the rock contains a large amount of silica, it is extremely hard, and preparing trilobites from the site is difficult since the rock does not separate well from the shell. Within the 15-meter section, only about two meters have been heavily collected, so occasionally this site will produce some extremely rare and one-of-a-kind specimens collected in float from the other layers.