Polariscope COE Test Card

Item Name:

Polariscope COE Test Card

SKU:

COETESTCARD

Description:

The Polariscope COE Test Card is a simple compatibility checker used to spot stress from mismatched glass in fused work. It’s made to be used with a light source by sandwiching your fused glass piece between the backlit films on the card. When the glass is compatible, you will not see a halo. If a halo appears, it indicates stress in the glass and signals incompatibility, helping you catch COE mismatch issues before they become cracks or failures in service.

How it is used:

• Place the test card on a bright, even light source such as a bright flashlight
• Sandwich the fused glass piece between the backlit films
• Look for a halo pattern
• No halo indicates compatibility
• A visible halo indicates stress and likely incompatibility