Hi Tim,
I came across this info:
Regularly clean your surfaces with a damp cloth. Dry-off worktops to avoid dull patches appearing where hard water and soap residues may have been left behind during daily use. A light neutral (PH7) detergent may be safely added.
Avoid the use of abrasive cleaners or scour pads. A spray cleaner, which can be applied to surfaces to clean and maintain the surface shine
Granite, and particularly marble, are porous materials even when the surfaces and edges have been polished. The stone is treated before leaving the factory to help resist staining. Therefore be careful of acidic and spirit based products such as wine, fruits and perfume. Care should also be taken with oil based products such as olive and cooking oils as these may stain if allowed to soak into the worktop. Should spillage occur, wipe off as soon as possible.
Worktops should not be brought into contact with strong acids or chemicals including paint stripper, brush cleaner, oven cleaner, nail varnish remover, degreasant or similar products.
Granite Kitchen Worktops Maintenance
Clean up spillages on granite immediately, especially those involving oil, strongly coloured foods and drinks and acidic spillages such as vinegar.
If a stain is slighty more resistant, use of mild or neutral detergents will usually be sufficient to remove it. To avoid any staining be sure to follow these basic rules :
Do not allow any build up of salt or detergent on your granite.
Never use abrasive cleaning products such as metal pads, scouring detergents and wire wool on granite as these can effect the finish over time. Also avoid alkaline and chlorine based cleaners and do not use bleach. Granite is easily maintained without the need for such abrasive cleaners.
Do not expose granite to excessive heat, it is best to have a tripod or similar to place your pans on when taken directly from the hob.
Over a period of time, it is natural for the sheen of your granite worktops to change depending on what usage it encounters. This can be easily restored by use of a granite polishing cream
Hope that helps!
Tracey.