Autumn reaches the studio long before the clocks change. The shelves start filling with pots that look like they have been standing under a beech tree: toffee browns, smoked amber, the dull green of a hazel leaf on the turn. The five glazes below are built on a single dependable cone 5–6 base, each coloured with a small addition of iron, rutile, copper or cobalt you may already have in the cupboard. They are intended for mugs, bowls and vases that get used, so the emphasis throughout is on a durable, fully matured surface. Mix small, test everything, and let your clay body have its say.

One base, five autumn moods

Every glaze here is the same base with a different colour addition, which means one bucket of base and five small test batches. It is a boron-fluxed, lead-free recipe that matures in oxidation at cone 5–6 (roughly 1180–1220°C) and sits well on most stoneware bodies. Mix the dry materials, sieve twice through an 80-mesh screen, then add water slowly until the glaze is about the consistency of single cream.

  • Potash feldspar — 30 parts
  • Borax frit (Ferro 3134 or equivalent) — 20 parts
  • Quartz — 20 parts
  • Whiting — 15 parts
  • Dolomite — 5 parts
  • China clay — 10 parts

That gives 100 parts by weight. The colour additions below are percentages added on top of those 100 parts, so 6% red iron oxide means 6g of oxide for every 100g of dry base. Treat the base as a starting point: if it comes out glossier than you want, add three to five parts more whiting and cool the kiln slowly from 1100°C down to 900°C. A slow cool is what coaxes out the satin surfaces and the rutile speckle.

1. Amber Ember

Base 100 + red iron oxide 6% + rutile 2%. A satin amber that thins to rust over rims, handles and carved lines, and darkens to treacle where it pools. Dip for three seconds, or give it two light passes with a spray gun. It is the most forgiving of the five and the one to start with if you are new to mixing your own. Mugs, small bowls and anything you want to feel warm in the hand.

2. Burnt Chestnut

Base 100 + red iron oxide 4% + rutile 3% + tin oxide 1.5%. The tin is a mild opacifier: enough to soften the colour into an oatmeal tan without flattening the speckle where the rutile gathers. Wide-rimmed bowls and plates suit it, because the texture reads across a flat surface. On tall forms it can look a little thin at the shoulder, so build the thickness evenly rather than chasing it afterwards.

3. Russet Tenmoku

Base 100 + red iron oxide 9% + cobalt carbonate 0.3%. Dark, glossy and almost black in the thickness, breaking to a warm rust over every edge. The cobalt is there to deepen the brown rather than to turn it blue; more than half a percent and the warmth disappears. These iron-rich glazes are fluid, so leave a generous bare margin above the foot and fire on a waster or a tile if you are unsure. Best on vases, bottles and slab-built forms.

4. Mossy Oak

Base 100 + copper carbonate 2.5% + rutile 4% + tin oxide 1%. A grey-green with rust speckle running through it, like lichen on a wall or a spruce branch after rain. It pools beautifully in a carved line, but it is also the one most likely to run if applied thickly. Keep it for exteriors: vases, jug rims, the outside of a serving bowl with a plain liner inside.

5. Dusky Plum

Base 100 + cobalt carbonate 0.4% + red iron oxide 3% + rutile 2%. A dusted mauve that reads as plum over dark stoneware and as cool grey over a pale body — the recipe that changes most from one clay to the next. Good on candlesticks, tumblers and the outsides of nestling bowls. Test it on every body you use before committing a large batch.

Getting the colour onto the pot

  1. Sieve the mixed glaze twice. Lumps become pinholes, and pinholes in a food surface are a problem, not a texture.
  2. Check the specific gravity with a hydrometer: around 1.45 for dipping, 1.30–1.35 for spraying.
  3. Fire a test tile on every clay body you use. The same glaze on a white stoneware and a dark grogged body are two different glazes.
  4. Aim for 0.5–0.8mm of dry glaze — a three-second dip, or two thin sprayed coats with drying time between.
  5. Wax the foot ring rather than wiping it. Wiped glaze leaves a ragged edge that chips.
  6. Record the thickness, the firing and the clay on the back of the tile.

Where a glaze sits matters as much as how thick it is. On a vertical mug wall, glaze thins as it runs down; on the inside base of a bowl, the same glaze will sit fat and glossy. If you want consistency across a set, dip mugs rim-down and bowls base-down, and keep to the same count of seconds every time.

Layering is where these recipes earn their keep. Amber Ember over Burnt Chestnut gives a deeper, smokier brown with a soft break at the rim. A thin pass of Dusky Plum over Mossy Oak turns the green toward slate. Try overlaps on a test tile first, and remember that the glaze underneath affects the one on top far more than the other way round.

Tip: two glazes at 0.4mm each behave very differently from one at 0.8mm. When layering, thin both, not just the top coat.

Food-safe, and where to be careful

A glaze is food-safe when it is fully matured, durable and does not release anything into food. In practice that means no lead, a proper cone 5–6 firing, and no crazing — those fine surface cracks give acidic food

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