The Science of Fire: pottery

SOUTH KINGSTOWN, R.I. (WLNE) — Humans have adapted fire for use thousands of years ago to cook and create necessities.

One of the earliest examples of this is pottery.

“What’s left from old civilizations? Pottery shards,” Peter Pots Pottery Owner Jeffrey Greene. :That will be what’s left of us.”

Greene is the second-generation owner of Peter Pots Pottery in West Kingston, which has been making pottery for 75 years.

To make each piece takes about a week.

“We try to avoid actual fire, but we use extreme heat,” Greene said. “We will fire our kilns at 2100 degrees. It’s about a 13 hour process getting up to that temperature and then once there, the power is turned off and it’s another 2 days to cool down before we can open the kiln.”

In the kiln, the heat takes out the water that makes it flexible.

Then it tightens the molecular structure of the clay, which shrinks and hardens it, turning it into a glass. This process is called vitrification.

Clay is normally fired twice, but Peter Pots has a special proprietary glaze applied before firing which only requires one.

“Our clay body in order to vitrify, has to reach 2100 degrees and the glaze is matched to that so that it flows together and you get a nice glassy and glossy finish,” Greene said.

(Track: Bates Pottery 6)

Going through this high heat process also makes Peter Pots Pottery dishwasher safe.

Peter Pots Pottery fired the kiln with gas instead of electricity until 1980. As a result, vintage pieces have a bluish tint to the brown glaze and are in high demand on auction sites.