Coal Macerals MA22 | Petrograhic Atlas | SIU

Southern Illinois University



Crelling's Petrographic Atlas of Coals and Carbons

College of Science


Frame ID: MA22
Sample ID: Brazil Block Seam, SW Indiana
Maceral Group: Liptinite
Maceral Type: Sporinite
Magnification: As given
Illuminator: Vertical
Objective: 50x oil
Polarizer: In
Analyzer: Out
Retarder Plate: Out
Filter: None
Important Features: Sporinite under white-light illumination showing a reflectance less than that of vitrinite
High Resolution Image (300 dpi)

Description: The dark feature in the center of the frame is sporinite. It is characterized by its low reflectance and bilateral symmetry.  The orange spot is due to internal reflections and is a common feature in megasporinite. A smaller sporinite maceral is also seen in the lower right.