Removing marks from ceramics

Presently cleaning up a bowl which I purchased in a dreadful state, the bowl not me. Much discoloration to the well and generally filthy. The outer area scratched and covered in marks. The process of giving it another life can be a bit long winded, but very satisfying.
Got me thinking back to when I visited the Moorcroft shop in Stoke (with family) 20 odd years back.
Everyone picking up vases with the musical accompaniment of rings clinking and scraping on pottery. Being my annoying self in asking folk to be careful.
The silver / dark like lines that you can end up with on some pieces can, I've found, be removed with a common rubber.
Water damage can be difficult to remove, though soda crystals are fairly effective with repeat applications.

If anyone has any good tips from their own experiences I'd be glad to hear them, as may others that frequent these boards.

For ages I tried cleaning an old, brown stained, bowl that just kept bleeding brown liquid. In the end I gave up. I think it must have been used as a beef dripping/gravy pot. The brown beef dripping had soaked into the clay under the glaze.

Well if you have small items I've been experimenting with an ultrasonic bath. If you have seen what it does to jewelry and bike parts you would be amazed. It essentially vibrates the water with sonic waves creating millions of tiny cavities in the water, you can see the dirt just float off from the crevices.

I just use hot (not boiling) water and a drop of washing up liquid.

DANGER EXPERIMENTAL - COULD DO AS MUCH HARM AS GOOD.
WOULD ONLY USE ON PIECES YOU HAVE GIVEN UP ON.

[Unrelated - found out today that vinegar removes rust stains from limestone floors - wet toolbox in kitchen]

NaomiM wrote:For ages I tried cleaning an old, brown stained, bowl that just kept bleeding brown liquid. In the end I gave up. I think it must have been used as a beef dripping/gravy pot. The brown beef dripping had soaked into the clay under the glaze.

Ohhh that's grim Naomi.
We used to get dripping on toast as kids, always a bit of a wrestle for the tasty brown stuff, not so much the greasy white fat. I'm a vegetarian now lol.

That sounds interesting Crawford, I'll do a bit of research, could be useful, thanks

It just depends what substance has caused the damage. As Naomi said, any kind of oil/fat/grease is a lost cause, as I've found with many of those large blue and white plates. Another lost cause are earthenwares that held spirits or liqueurs, like those
Wade barrels and the Drioli bottles. Earthenware oil and vinegar bottles can be similar.

Having said all that, (thin) bleach is great, particularly on things like Poole or any
pottery that crazes badly, like Portmeirion, Midwinter etc.
Immerse in a plastic bath, sometimes for a couple of weeks, to let it really soak in,
then warm up with a gentle heat to burn it off, and get rid of the smell. Rinse off any
crystals and wash & heat again.
Bleach also gives almost instant results on stained teapots.
2 litre bottles are literally a few pence from all major supermarkets.

Strong Peroxide, as used by the hairdressing trade was really the best as it was
odourless and would shift anything, but I don't think it is available anymore due
to legislation.

I do use wood bleach (Oxalic acid) on furniture, though I've never tried it on pot
as it's pricey and only comes in tiny bottles, but would probably work aswell.

Metal marks on tableware, or those TG Green mixing bowls, are easily removed
with liquid metal polish.

Cheap bathroom cream cleaner will get most surface mucK off, eg. foot rims.

You can still get peroxide for hair/ antiseptic - but maybe not as strong as before.

Some great tips there Denby, thank you for going to the trouble of putting it all down, much appreciated

So some of the little things I put in my Ultrasonic bath came of gleaming clean and new looking. A bit like a pastie and a microwave with water molecules inside the pastie being given energy the bath does a very good job. So good that I asked myself do you want your pottery sparkling clean - looking like it was made yesterday. I started to think not. It's OK for jewelry but perhaps not ceramics.

AGAIN DONT USE THIS METHOD ON PERCIOUS ITEMS IT MAY DAMAGE THE CERAMICS / OPEN UP EXISTING CRACKS / UNTESTED

Thanks for the advice Crawford, could be very useful for the right sort of item, as you mention.

I'm very set in my ways with ceramics, whilst I am ok with my own dust, I'm not ok with second hand pots and anything that I buy to display gets cleaned to within an inch of its life, albeit very gently cleaned.

I leave some things dirty... I'll get you a shocking pic

One downside of cleaning is of course damage being revealed that you had
missed when you bought it!

denbydump wrote:One downside of cleaning is of course damage being revealed that you had
missed when you bought it!

So true, I've had a couple of nasty surprises.


I'm waiting with baited breath Crawford, with scourer in hand

Took time to get to it. Under elec meter. A 500mm high Ian Gregory pub, 'Duke of York'. Uncleaned except for the cat. Must have been in someone's loft or garage or shed for thirty years judging by the dust.

looks great! I'm well Jell

You don't mind the dust?

With or without dust, that is fantastic. My eyes are also a little green with envy

Well in a few hundred years they may be able to get DNA and clone the person from his dust! Uncleaned things will be worth millions!

Half human. Half dust mite

Third garage rat!

A new superhero - the Mite-y-Ratman :D

Wasn't he the infamous slum landlord?

Of course I should add the rider, that many items of pottery should not be cleaned
if they are painted or enamelled or also any Gilding/Silvering or damage will result.
This would include a lot of 1920s/30s pottery like Clarice/Susie Cooper/Grays/
Charlotte Rhead/Bretby/Brentleigh etc. where the decoration is unglazed.

True. I once tried washing a Japanese satsuma vase with gold netting that just lifted off