Pyrite Sun in Matrix Value Guide

Pyrite Suns, also known as Miner's Dollars, are remarkable radial crystal formations found exclusively within coal mines near Sparta, Illinois. These specimens represent a rare geological phenomenon from the Pennsylvanian Period where extreme pressure forced iron disulfide to grow in flattened, sunburst disks rather than standard cubes.

What affects the value of Pyrite Sun in Matrix?

• The diameter and symmetry of the pyrite sun, with larger, perfectly circular disks commanding higher prices.
• The degree of contrast between the bright metallic pyrite and the dark shale matrix.
• Overall preservation of the shale, as the matrix is prone to splitting or crumbling if not handled correctly.
• The presence of a full, unbroken radial 'sun' without missing sections or heavy oxidation.

How to Identify Pyrite Sun in Matrix?

• Look for a distinct radial, starburst pattern of brassy gold pyrite crystals emanating from a central point.
• Verify the host material is a dark, fine-grained carbonaceous shale typical of the Illinois coal beds.
• Check for the flattened, disk-like structure which distinguishes these from common cubic or framboidal pyrite.
• Authentic examples will show the pyrite naturally embedded or 'in situ' within the shale layers rather than glued.

History of Pyrite Sun in Matrix

These unique mineral formations, also known as Miner's Dollars, were primarily discovered in coal mines near Sparta, Illinois. They formed approximately 300 million years ago during the Pennsylvanian Period. The extreme pressure between layers of shale forced the iron disulfide to crystallize in a flattened, radiating disk rather than the typical cubic structure associated with pyrite.