St. Clair is famous for the white appearance of their plant fossils which caused by aluminum silicate or pyrophyllite. This first fossil is Alethopteris.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi98amPYyx4qPnmEGTUidznGtA6BAgl9LG-49nH-wnUcsf99MBuvmGORYivHY2UeL4OM8MaQIhcFblDi6FkNbQlywECYS7DQwtMdFHLD8eXzfsikoYAPq_iki4shpgqlNuZSDMdwOIh9OtH/s400/alethopteris_st_clair_pa.jpg)
This second fossil is a Asterophyllites. It could be of the species Asterophyllites charaeformis.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhzNfSGdGvqfnqFslwBp-SX82WG5P6bl02-1Z6k_UA6UV93a5lTcd2uLng8R3MS3oDqOmN1LYAnh_ICDJmpPQ8xKHc1cmSk4d1-UYkCJrCvPUGIQYTPPbRDUooqQyZGfFnsIWBfcbLZrwaT/s400/asterophyllites_st_clair_pa.jpg)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiTbbeYXXDhIPWA4c9LQfmYej9CRUti3XuKRbY9zSiLihpBhwOyJxw-lz83fUoxxlE-09lISEWjo4-LArS6gNp4h4uBAhFPc7PnuW1p7LKZAAxZ8gfxjOOA_oCSC8JAPBaCfxIiAq7HcJ9w/s400/sphenophyllum.jpg)
This last fossil plant is unidentified.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqacb_ou-ecsteE1DL-VmOhulDAQtXVQS01yLW9brR9z9YXibHoYtBVA9TpmgsJy_qJQ9y821dp83TbTpkgwuqD3VGO5t9uThAss_0FlYc350CnO3jeL2AtRurO8ZoJZS5nrAdXwfnTaWZ/s400/Odd-fern_st_clair_pa.jpg)