Garden Furniture water stains

Left a large glass bowl sitting on a teak garden table last summer, which unfortunately has left a dark 6" diameter stain on the table surface, presumably as rainwater with the usual air pollutants has run off the bowl and settled on the wood before eventually evaporating away.

Any ideas on how to tackle the stain? Have already tried simple cleaning with garden furniture cleaner and then re-oiling, but no joy. Have been reading about wood bleach and /or oxalic acid. Anybody have experience of these?

TIA

May not be a dark stain. It could be the rest of the table which has bleached in the sun's UV.

luggsie

Have used oxalic acid before on pine which had darkened due to it being denatured when the paint was left to flake for some years. It worked to a good extent on pine, not a total panacea but definitely lightened the darkened area. The oxalic acid was manufactued by 'Liberon', sold as wood bleach. The problem I foresee with your situation is that you are trying to remove a ring stain, and that may require careful application of the acid to avoid ending up with a bleached area. Dunno, I'm probably exaggerating the effects of oxalic acid, it's not that strong, and I've no experience of its effect on teak.

Andy.