Firstly if you think you have a very expensive piece that needs cleaning take it to a professional to have it done for you.
Secondly if you are not sure how something might work when using any of these suggested methods, do a test area on a small insignificant area of your piece. Be very careful with areas that are gold painted or cold glazed or you might remove the colour.
* All these suggestions are for glazed items, glass items and non porous items.
* Always use protective gloves and some form of eye protection when cleaning.
* Never put your quality, vintage or antique china or glass in the dishwasher. Precious glass and china should only be washed by hand in warm water.
Before doing any cleaning protect your items. You might think you are careful, but it doesn't take much to chip or crack something. Cover your sink and the tap in a dish cloth, clear away unwanted clutter around your area and make sure that every thing is at hand before you begin.
If the items only need a little bit of cleaning, use a soft cotton cloth and mild detergent. Rinse in warm water and allow the items to dry naturally. If you have to dry them, use a soft cotton cloth or a shammy you would use to clean a car, but not one that has been impregnated with chemicals.
Glass that has a build up of salts and minerals on the bottom can be cleaned with denture cleaning products. Just drop a tablet or powder in the bottom and let it fizz up. Leave over night and in the morning clean with warm water.
Pure vinegar is also good for that white salt look in the bottom of a glass. Use pure white vinegar only, fill the item with it and leave over night. It the item is not able to be filled, soak cotton wool in vinegar and stick them to the area and let it dry a bit. The cotton wool balls with help to draw in the salts and minerals and make it easier to clean your item with a mild washing afterwards.
Give glass a rub with a soft cloth and methylated spirits. This often brings back a nice shine.
If glass doesn't get that polished look you can use jewellers rouge to buff up the glass or crystal. Put the rouge on a soft cotton cloth and polish as if you would shoes.
* Never use bleach on china or porcelain.
Hydrogen Peroxide is not bleach and used carefully can have some fantastic results.
* Always wear gloves, a mask and eye protection.
You can use the hairdresser grade of liquid or cream peroxide cut at 1 water to 3 parts peroxide, soak it on a cotton wool ball and place these over the area that needs to be cleaned, such as areas of fine crazing that are yellow. The cotton wool balls absorb the dirt into them. To keep it all moist, you can rap it in plastic, but we usually put items in a plastic box and leave them. Sometimes it works overnight, but heavy stains can take up to a week to really come clean.
If the item is very dirty or something like a butter dish and it is the grease you are trying to absorb out, then you will need to change the cotton balls several times over 3 to 4 days.
You can help decrease the time to clean by putting the item with the cotton soaked balls in the oven and bring the temperature up to about 100c. Don't use a fan forced oven it heats too quickly and don't use a gas oven. Leave it for about half an hour and check. You may have to do this a couple of times with clean peroxide and cotton balls.
We actually use a commercial grade peroxide and cut it by a third. But it is better to take things slowly and see what works best for you. We like the commercial grade better as it doesn't smell so pungent.
* Never put peroxide on gold trimming or cold glazes.
Always wash in warm water after cleaning.
If you spill peroxide on you, wash immediately in cold water. It will burn your skin and always use in a well ventilated area. Keep it away from children.
* Cleaning a cold glaze item is very hard and best left for the professionals.
If you have a dull surface on a matt flat finish glaze on pottery, to give it a slight sheen and bring back the colour use a soft cotton cloth with jewelers rouge. Don't over rub.
Tea cups and coffee mugs that have that ring stain on the bottom can sometimes be cleaned by painting the area heavily with PVC glue and letting it dry. When it dries just peal off and the dirt will come with it. Wash after cleaning.
China, glass and crystal need to be washed regularly, even if they are not being used. It helps them to breathe. Clean them every few months for the best results in warm water without detergent and allow them to dry naturally.
To remove permanent marker from the bottom of something use a toothbrush with solvol soap and gently scrub in a circular motion. Acetone, or nail polish remover also works but be careful not to drip it on the glaze. Ink and pencil can sometimes be removed with a pencil rubber. A rubber also works on removing newspaper marks.
Eucalyptus oil will get off the sticker residue.
Hard to get at dust in a figurine can easily be cleaned by a light spray of rubbing alcohol you can get from the chemist. The dirt slides out of the area and because the alcohol evaporates it leaves the area nice and clean. Then clean the remaining area carefully in warm water and allow to dry naturally.