Titanium Dioxide

They give different whites. Tin oxide gives a soft, warm white and costs the most. Ultrox, a zircon opacifier, gives a bright, cool white at a low cost. Titanium dioxide gives a creamy, semi-opaque white and can add a satin surface with tiny crystals. For a bright, solid white, start with Ultrox.

Start with 5 grams for every 100 grams of a dry clear base glaze (5%) for a soft, semi-opaque white. Around 8 to 10%, glazes tend to turn satin or matte. Make test tiles at 3%, 5% and 8% to see the range.

Titanium encourages small crystals to grow as the glaze cools, especially in runny glazes and slow-cooling kilns. That gives the mottled, variegated look many potters want. If you don't want it, use less titanium or let the kiln cool faster.

No. Rutile is titanium with iron in it, so it adds color and movement. Titanium dioxide is titanium without the iron and adds no color of its own. You can't swap one for the other gram for gram.

Glaze and clay recipes go by weight, not by volume, and they don't count water. Each ingredient is a share of the dry total. 2% means 2 grams for every 100 grams of dry ingredients. For a 500-gram batch, that's 10 grams. Colors and opacifiers are often listed as extras on top of a recipe that adds up to 100, written like "+2" or "add 2%." Weigh those the same way: 2 grams for every 100 grams of the base recipe. A digital scale that reads to 0.1 gram makes small amounts easy.

A test tile is a small piece of the clay you use, glazed and fired just like your real work. Raw materials vary from bag to bag, and results also change with your clay, how thick you apply the glaze and how your kiln fires. A test tile is the only way to know what you'll get before you glaze a whole batch of pots. Write what's on each tile on the back (an underglaze pencil works), and keep notes so you can repeat what works.

Yes, whenever you handle the dry powder. Fine dust is the main hazard with most raw materials, and some can harm your lungs over time. Wear a NIOSH-approved respirator (N95 or better) while you weigh and mix. A basic dust mask that isn't N95-rated won't protect you. Once a material is mixed with water, dust is much less of a problem, but wipe up spills with a wet sponge before they dry, and mop instead of sweeping. Don't eat or drink while you work, and wash your hands afterward. Check each product's Safety section for anything extra that material needs.