A black form of iron oxide for browns, blacks, speckles and dark clay bodies.
You must test before you use it, at any scale. Raw materials, mined or man-made, are not consistent. Color, strength, particle size and chemistry can change from one bag to the next and from one supplier to another, even when the name on the bag stays the same. Before you use this material in a glaze, slip or clay body of any size, mix a small test batch, fire it on your own clay in your own kiln, and check the results.
What it is
A black iron powder. In a glaze it gives the same family of colors as red iron oxide: ambers, browns and blacks. Its grains are a little coarser, which makes it good for speckles and dark slips.
Getting started
- Use it like red iron oxide. Start at 2 to 4% in a glaze (2 to 4 grams per 100 grams of dry glaze) and test.
- For speckles, stir it into the glaze or clay without sieving it out.
- It can replace red iron oxide nearly one-for-one by weight, but test first.
For glaze formulators
- Black iron oxide, Fe₃O₄. Slightly more iron by weight than Fe₂O₃.
- Coarser than red iron oxide. Mill or sieve for even color; leave it coarse for specks.
- Ends up as Fe₂O₃ in oxidation and FeO in reduction, so it fires much like red iron oxide.
Safety
- Low toxicity, but don't breathe the dust. Wear a NIOSH-approved respirator (N95 or better) when handling it dry, and clean up with a wet sponge, not a broom.
- It stains skin, clothes and work surfaces.
Sizes & pricing
| Size | Price | Per lb | |
|---|---|---|---|
| 1 lb | $1.45 | $1.45 | Add to cart |
| 5 lb | $6.50 | $1.30 | Add to cart |
| 10 lb | $12.00 | $1.20 | Add to cart |
| 25 lb | $27.50 | $1.10 | Add to cart |
| 50 lb bag | $38.50 | $0.77 | Add to cart |
Full bags mix and match. Every full bag in your order, of any raw material, adds up. That total sets the price of every bag. Smaller sizes don't count.
| Full bags in your order | Price per 50 lb bag | Per lb |
|---|---|---|
| Under 500 lb | $38.50 | $0.77 |
| 500 lb and up | $37.50 | $0.75 |
| 2,000 lb and up | $37.00 | $0.74 |
| 6,000 lb and up | $36.00 | $0.72 |
| 12,000 lb and up | $35.50 | $0.71 |
Prices from our October 23, 2026 price list.
Frequently Asked Questions
CUSTOMER REVIEWS - Q&A
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