Ceramic herb markers - an easy process to repeat

Being my most popular item on my Etsy shop (not exactly a lot of competition there though) I decided to start producing these markers on a larger scale, and attempt to fire a whole kiln full in one go. So I got to work creating as many markers as I could to fill the kiln.

Here's the first six sets drying on a plaster bat.

Stoneware herb markers at 'leather hard' stage

Here's how I create the markers (mostly written for me to refer to in the future). I roll out the slab to a depth of 6mm, using wooden beading to get the correct thickness. Each marker is based on a 13cm long strip, which is cut using the width of the wooden beading (approx. 3cm). The tip of each marker is then cut to a point with a wet blade. I've found that the wet (clean) blade makes a much smoother and easier cut that a dry blade. I use an old kitchen knife for this. Oh and the clay I'm using is crank (stoneware) which is grogged and gives the markers a nice grainy rustic appearance.

I then use hot metal type to imprint the lettering. For these I use 48pt perpetua lowercase. I imprint the whole word (or as much as possible with one of each letter) in one go -  this keeps it a bit neater and stops individual letters being 'squashed out' by the next letter. I find that leaving the markers to part-dry on the plaster bat gives a cleaner and neater imprint. If the clay is too wet it can stick to the lettering, or even come off in the enclosed bits of the characters (e.g. in the 'o', 'p', 'b' etc.)

Once the markers are completely dry they are bisque fired:

1. Up to 600ºc at 150ºc per hour
2. From 600c to 950ºc at full ramp
3. Cool down

With just four shelves in the kiln I managed to get thirteen sets of five markers in the kiln.

The next stage is to apply the stain to the lettering. For this I use copper oxide powder mixed with water, just a tiny amount to get the powder into a suspension so I can pick it up with a watercolour brush. I apply this to the indented lettering allowing it to pool in the letters but not worrying too much if it gets on the surface of the marker.

Here's what they look like at this stage

Stoneware herb markers - bisque fired with copper oxide stain applied

The next step is the wipe the excess oxide off the surface. This is best done with a moist (clean) sponge. The bisque fired clay will try to absorb the oxide, so its best to wipe this off with one clean stroke, I've found that pushing the sponge onto the surface to release a small amount of water 'pushes' the oxide into the lettering and then the rest wipes away easily.

Finally the glaze is applied. I've switched to using P2227 from Potterycrafts. It's semi-opaque and works well with the stain and also gives the clay a speckled 'oatmeal' appearance. I dip the upper side of each marker into a shallow tray of glaze, wait for it to dry then wipe any excess from the underside so it doesn't stick to the kiln shelf. This glaze doesn't run so you don't need to worry about leaving too much of a gap between the glaze and the bottom.

I place these directly on a (batt-washed) kiln shelf and fire them:

1. Up to 600ºc at 150ºc per hour
2. From 600c to 1260ºc at full ramp
3. No soak
4. Cool down

Results and photos of the finished markers in a follow-on blog post.