Ah, matey! Dredged up something from the bottom of the ocean have we? After the salt firing, some of the thinner threads of slip-coated fiberglass either burnt, melted, or dissolved away. Worth trying again? Definitely.
A dinnerware set I finished recently. The glaze combination is an iron-rich Tenmoku Glaze applied over an Iron-Blue Celadon glaze. The celadon recipe I used was Elain Coleman's recipe as published in Ceramics Monthly. If you click on the picture it will take you to my Flickr photos, where there are more pictures available for viewing and download.
Finally, a published glaze test. Interested in using natural materials, I've been experimenting with wood ash and clay from a local creek, and a feldspar (Canadian Nepheline Syenite). My greatest surprise was in the tile in the bottom right corner, which had the largest percentage of nepheline syenite. To see a larger image , click on the picture.
Here is a second set of tests. Click to see a larger version of the image. Sanders Celadon is a recipe borrowed from Ash Glazes by Phil Rogers -Paul Christensen
Sculptural Mug Cup thrown with fiberglass wedged into cone 10 B-Mix, fiberglass cloth dipped in slip and applied to exterior of form, various slips and engobes applied when leather hard.