Graeme
This is a bit tricky to answer because it depends on the size of spill or splash and how quickly the customer reacts as the problem here is the riven or rough surface! Ordinarily if a surface has been sealed with a premium water based impregnating sealer and the customer reacts relatively quickly then a bit of Fairy, nailbrush, some warm water and a decent Microfibre cloth should lift an oil stain or grease spill if treated quickly. I don't think a solvent is required personally. However if it is a decent spill and it has been left for any length of time it may then require a high alkaline, a sealing & coating remover or even a poultice if it's really gone deep.
Kev Martin
Marblelife Ltd
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