Glaze Guidelines for Open Studio

Glazing is one of the most satisfying, yet volatile elements in ceramics. To ensure the success of our members and safety of the studio equipment, all studio members must follow these glaze guidelines.

  • The lower 1/4 inch of piece and the foot must be free of glaze before glaze firing.

  • Glaze should be applied in accordance with its unique properties (example: glazes and combinations prone to movement should not be applied as heavily to the bottom half of the piece).

  • Utilize standard glaze application techniques and tools for brushing and dipping. No spray application will be allowed in the studio.

  • Luster is not permitted.

  • We do not provide stilts for firing but you can provide your own if you would like us to stilt your piece while firing.

Proper Glaze Application

  • NPC will always glaze fire at cone 5 and bisque fire at cone 04.

  • NPC will only fire pieces with mid-range (cone 4-6) glazes applied.

  • Commercially made glazes only (must be AP or CL certified).

  • We will not fire commercial glazes that intentionally crawl, flake, shiver, foam, crater, pit, or blister including Ritual Brand glazes, and Mayco’s Magma glazes.

  • Glazes made by regional pottery retailers are allowed (Seattle Pottery Supply, Clay Art Center, Georgies).

  • Glazes should be recommended for use on cone 04 bisque.

  • If unsure if your glaze is appropriate for NPC firing, please email admin@nwpotterycollective.com or speak with staff during open studio hours.

  • We do not allow homemade glazes.

Commercial Cone 4 - 6 Mid-Range Glazes Only

Northwest Pottery Collective reserves the right to not fire pieces that violate these guidelines in its kilns