Sunday, September 26, 2010
I know it sounds like a major moral question for modern living...but it's not. And, I'm not talking about the 3-R environmental concept of reduce (although it's a good idea for us all).
Reduction, as you may know, is the combustion of fuel (a combination of hydrogen, carbon and oxygen, usually found in the form of gas, oil or wood) in a relative lack of oxygen. When this happens in your car engine (too much gas, not enough oxygen), it is called incomplete combustion and it is a bad thing for your car and the environment. But when it happens in a potter's kiln, it is a good thing! And here is why.....
It's all about that periodic table we saw in high school. Yes, art really is about science! Remember the low part in the centre of the table given the group name "transition metals". One thing they have in common is they all have several oxidized states (i.e., the electrons on the outer surface of the atom move). And when the metal changes oxidized states, they change colour! Now I have the attention of the artists!
All clay, be it earthenware, stoneware or porcelain, contains iron. Most typically in the form of ferric (or iron (III)) oxide, or more commonly called rust. It is a red-brown colour and is most typically found on your car! This is the most commonly found type of iron oxide because the world around us is plentiful with oxygen.
If we are able to remove the oxygen around us, as we can in a reducing kiln, we convert the ferric iron (III) oxide (red) to ferrous iron (II) oxide (black). So, this little bit of chemical magic seems intriguing, but why do potters care about this change of colour? Can't we simply change the colour of clay with stains and glazes on the surface? Sure we can. But there is a key issue that make reduction an essential element in functional tableware production...it is porosity of the clay body (underneath the surface decoration)!
Potters, who make tableware, as opposed to cooking ware, want the lowest porosity possible in their finished pots. This makes them dishwasher and microwave safe. Porosity is reduced to an almost insignificant level when the clay body is well fluxed (the silica in the clay is turning to glass). And here's the bottom line....black iron is a flux, red iron is not. That little transitioning electron makes a huge difference to the nature and quality of the fired clay.
Pots fired in an electric, oxidized kiln will seldom have the same low porosity as pots fired in a fueled, reduced kiln. And you will be less likely to get the crystal ping sound when you flick it with your finger. And your customers will not be disappointed by pots that break in the dishwasher or microwave!
Sunday, September 19, 2010
For those that couldn't make it to the lantern festival, here is a taste of what you missed. Here's a close up of a few of the lanterns before the sun set.
My installation, titled "Chain Reaction" was photographed by lots of photographers, who I am sure did a better job of shooting it in the dark than me. Here it is illuminated.
Saturday, September 18, 2010
I am joining my fellow artists at the Kingston Glass Studio and Gallery at 56 Queen Street from 7-10 pm on Thursday 23 September to exhibit our art work as part of the big roving party that Downtown Kingston has organized.
I am taking my potter's wheel and demonstrating...and if you are brave, you can try yourself!
There will be tons of great art, lots of fabulous artists and food and drink. Please join us! For more details and the map of galleries involved please check out the link.
HARS (HIC/AIDS REgional Services) has organized A Lantern Festival and walk in the park in Kingston again this year. To compliment the awareness and funds raising effort, several artist have developed installation art that is illuminated by candles. Please join us this evening for a fun, family event in the park at twilight.
Here is a photo of my installation named "Chain Reaction". You can see it illuminated tonight!
Sunday, September 5, 2010
I just had the most awesome time last week in greater metropolitan Combermere (on the Madawaska River near Barry's Bay). I was asked to go to Madonna House to offer a pottery workshop to a group of folks that live in a really exciting community. They focus on prayers, meditation and caring for each other. Their vow of poverty frees them up from worldly concerns and allows them to focus on the stuff that really matters....other people! It was so refreshing to spend time (and work hard -14 hour days!) with people that are truly honest and thoughtful....something that is often missing in our fast paced world.
We had lots of fun and made tons of pottery and fired their new (to them, but used and donated by a patron) kiln.
Special thanks to the folks at St Raphael's and the rest of the community that supported during this workshop.