Why does teak sometimes turns black or dark gray?
The black spots on teak are commonly mistaken for dirt getting stuck in the wood. However, the black spots on teak are actually mould and mildew which are growing in the wood and teak oil which was baked by the sun. Golden Teak Cleaner will remove any mould and mildew that may have accumulated. However, if teak-oil is used again the problem is likely to reoccur as the mould and mildew will have food again! Teak becomes gray because of Ultra-Violet rays from the sun. This process can be prevented by treating teak with Golden Teak Protector, which contains unique, expensive UV absorbers and reflectors.