What is sands in possessive form?

The possessive form for the plural noun sands is sands'.

NOTE: The noun sand is an uncountable (mass) noun as a Word for a substance. The plural form, sands, is used only for 'types of' or 'kinds of', or for an area of sand such as a beach or a desert. An example sentence for the plural possessive form:

Our sands are priced by the ton. The sands' listed prices include delivery.