Glaze material · Clays
Barnard slip
Also sold as: Blackbird
An iron- and manganese-rich slip clay, a bit more fluxed than Albany.
In published recipes
Used in 75 of 10,859 glaze recipes (0.7%)
Typical amount when present
20% of the dry batch — half of recipes fall between 5% and 45%.
Fired surface of those recipes
Glossy 59% · Semi-glossy 18% · Matte 11% · Semi-matte 11%
Most often mixed with
Materials that appear in the same recipes most often.
What potters should know
Named among the go-to substitutes for Albany slip. Its manganese content earns the manganese handling caution.
Handling and safety
Contains manganese compounds. Chronic inhalation causes manganism (neurotoxicity); use respiratory protection during dry mixing.
Crystalline silica: the primary respiratory hazard in a ceramic studio (silicosis with chronic exposure). Wet processes, ventilation and a fitted respirator when dry.
Dry ceramic materials generate respirable silica dust. Use a NIOSH-approved N95 or P100 respirator and adequate ventilation when mixing dry, and wet-clean surfaces.
This information is provided for planning purposes and is derived from publicly available sources including OSHA regulations, NIOSH guidance, and manufacturer safety data sheets. It does not constitute professional safety advice. Consult your material suppliers' SDS documents and applicable local regulations for authoritative safety guidance.
Questions
- How much Barnard slip do potters use in a glaze?
- Across 75 published glaze recipes containing it, the typical amount is 20% of the dry batch, with half of recipes between 5% and 45%. Colorants and additives sit far lower than fluxes and glass formers; treat these as a range to test around, not a target.
- What cone is Barnard slip used at?
- It appears in recipes across the range; the most common cones among published recipes are cone 10, cone 6, cone 9. Where a material sits depends on the rest of the recipe more than on the material itself.
- Is Barnard slip safe to use?
- It carries a specific hazard flag: Contains manganese compounds. Chronic inhalation causes manganism (neurotoxicity); use respiratory protection during dry mixing. Read the supplier's SDS and follow local rules before using it, and never assume a glaze is food-safe without testing.
Related materials
| Glaze material | recipes | typical |
|---|---|---|
| Albany slip | 163 | 60% |
Sources. Usage figures are computed by Claybench over 10,859 glaze recipes compiled from publicly shared community recipe collections (snapshot 2026-02-27) — counts only; no recipe is reproduced, and the figures describe that collection, not every recipe in existence. Material roles and notes are paraphrased from Linda Arbuckle's Ceramic Materials handout unless noted. Hazard notes summarise supplier SDS guidance; read the SDS for the product you buy.
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