This places it in the upper Silurian age.

This is from the Silurian age at 414 Mya.

In the Hall area the rocks are all Silurian age volcanic rocks.

It could not be otherwise, for in the Silurian age the seas contained at least fifteen hundred vegetable and animal species.

Gilmore is built on volcanic rocks from the Silurian age.

These are from the Silurian age at 414 Mya.

All of these rock types are from the Silurian age.

Deep underneath are volcanic rocks from the Silurian age at 414 Mya.

Most of the sequence is middle Cambrian to lower Silurian age.

It has only been found in rocks of Silurian age.