Mould on wood after removing lacquer

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aet1

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I have quite an old table - looks like the metal hinge part was made by a blacksmith (the top revolves and fold out to twice the size).
As the top was in a very bad way - "distressing" is nothing to the condition of this I've sanded it to bare wood.
After ages getting a good finish yesterday I damped the top to raise the grain.
This morning there is mould on it! I did see some dark bits in the grain after I took the lacquer off.
I wonder if the spores were lacquered over and taking it off has given them a new lease of life.
I can start sanding again - but it would be sensible to kill off any mould - but can't use anything that will bleach the wood.
Any suggestions please?
 

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looks more like a metal stain, water could have reacted with some iron dust and the tannins in the wood? Oxalic acid is the normal choice for bleaching wood, but test on an inconspicuous area first.
 
looks more like a metal stain, water could have reacted with some iron dust and the tannins in the wood? Oxalic acid is the normal choice for bleaching wood, but test on an inconspicuous area first.
Thanks for your quick reply,
I did wonder about metal first, I suppose I could try to scrape some off and test it.
I don't want to use anything that will bleach the wood as it will not match the rest.
 
Sorry my poor reading, I thought you were looking for a bleach recommendation! A mould killer is likely 95%+ water so I'd sand then apply the mould killer, if it comes back you know it's not mould.
 
Looks like it is mould. I'm trying some "natural" ideas on a scrap of sapele, white vinegar, white vinegar with bicarbonate of soda added. As it's a solid top I can sand more off but want to make sure any spores are dead. This time I won't try to raise the grain with water - I understand white spirit does the job and makes sure the surface is free of any oil too.
 
Back to the drawing board! I sanded, went over with white vinegar (making sure I did this and have left the top indoors as my garage/workshop is rather humid).
I had toyed with polyurethane varnish, I thought of lacquer ... then today I had a google to find a similar table, I thought it is old but it turns out to be George 3III, the only furniture I have older than me.
Now I have a responsibility to make it proper, so I've ordered some mahogany grain filler, and it looks like I might French polish, something I have not done for over 40 years.
 
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