The blackness is caused by minerals in the water. This can be removed with bleach. The woodworkers choice is oxalic acid but a substitute is laundry bleach to remove the black color. The surface must be sanded, a matching color of stain added and a new finish applied to those areas. Not easy but do-able. Maybe an insurance claim?
--Previous Message-- : Last night, our basement leaked and my wood : bedroom set sat on a soaked carpet for : about one to two hours. The wood on the : legs of my bed, nightstand, and armoire do : not appear to be damaged but they have : turned black where they got wet (the : bedroom set is American Signature and has : a light or natural finish). What causes : this? Did the finish or the wood turn : black? Will it get moldy? Do I need to : sand and refinish the legs? Any : suggestions would be greatly appreciated. :