how to clean a hairline crack on a vase?
Answers:
There is a "CREEP" type glue that goes into cracked ceramics. Inquire at a good hardware store. Apparently it creeps by capillary action, and the excess is wiped off with a damp cloth.
It is called Captain Tolleys creeping crack cure. PO BOX 967 London phone 071 9242817
Other answers:
Clean the crack with a toothbrush to get any dirt or grime out.
Run a bead of white glue and smooth it with a damp fingertip.
Wipe away any excess with a lint-free cloth or rag.
After the glue has dried, remove any outside of the crack with your fingernail.
If the vase is not white, after filling the crack try experimenting with a permanent marker that matches the color and lightly trace it down the crack to blend it back in.
Clean the crack with a toothbrush to get any dirt or grime out.
Run a bead of white glue and smooth it with a damp fingertip.
Wipe away any excess with a lint-free cloth or rag.
After the glue has dried, remove any outside of the crack with your fingernail.
If the vase is not white, after filling the crack try experimenting with a permanent marker that matches the color and lightly trace it down the crack to blend it back in.
You probably want to leave it alone. If you add anything to it the vase will weaken. The material will soak up any cleaner. If you must clean try Dawn soap diluted in lots of water and wipe with a sponge. Dipping the sponge in the soap and water.
I doubt very much that you can clean it. I'd try soap and water, but the water could soak into the crack and discolour the porcelain underneath the glaze. It could take a long time to dry out.
Whatever you do, please don't try running paint or glue into the crack. This will almost certainly look worse than the crack, and will destroy any value that the vase has.
Make a paste of bicarbonate of soda and gently rub along the crack use your finger or a lint cloth. Wash off with luke warm water and gentle wipe dry. Do not attempt any other method as it may damage the vase further. However, If you consider the vase to be of value seek advice from a professional antique restorer.
Good luck!
Peroxide. Then milk and white glue mixed together.