How To Iridize Glass - Go Fusing Blog
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How To Iridize Glass

How to use or make Iridized Glass 
Updated 1/2020
Author: Ann Sanborn

Iridized glass is beautiful! It shimmers and sparkles, much like the qualities of dichroic glass as it depends on reflections of light but it is a more subtle shimmer!

Iridized glass can be smooth, in a pattern or even textured.

You can obtain different effects by simple placement of the iridized coating facedown, up or sandwiched it between layers of glass.

An irid surface affects the way the glass heats and cools so it is best to use conservative firing schedules and test a sample whenever possible.

Different Manufacturers of Iridized Glass:

Spectrum's Glass Irid can  be fired face up but if performing a full fuse then use Irid side down to prevent burn off.
Note: As of 2018 the product line was sold to Oceanside Glass Tile and is not in product as of 1/2020 so you will have to find old stock.

Uroboros Glass Studio made a COE 96 Irid that was very stronger and can be fired Irid side up.
Note: As of 2018 the product line was sold to Oceanside Glass Tile and is not in product as of 1/2020 so you will have to find old stock.

Wissmach Glass makes Sheet Glass call Luminescent. This version of an Iridized glass must be fire Face Down or covered with a fiber blanket, face up in order to not burn off.

All though Iridized glass ican be purchased from your glass distributor, you can also try your hand at creating your own iridized glass AND this technique also work with float glass!

  • Fill an airbrush bottle about 2/3 full with rubbing alcohol.
  • Add 1 drop dishwashing liquid.
  • Add enough mica powder to make a good mix. (Not thick but still have good color.)
  • Use an airbrush on a light setting.
  • Spray several light coats. (Avoid heavy coats of mica because it will pool randomly on your glass.)
  • Allow it to dry and fire your glass in the kiln.

NOTE: This process works best on dark colored, opaque glass and results in an iridescent glass after kiln firing your glass to permanently bond to the surface.

We carry a sample set with a variety of mica powder colors #44305.

Tip: When you buy mica powders make sure that you don't get the ones that have plastics in them, ours does not.


  • You do not need to fire at higher temperatures to permanently bond an Irid coating to glass.
  • Do not fire iridescent glass face down on to another irid glass. Micas do not like to fuse together glass fusing temperatures.
  • When using iridescent glass as a base glass, place irid side up.
  • The surface of an irid layer will look best at a tack fuse versus a full fused.