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I have an indian rosewood back with some tiny streaking of white material. Is this calcium? I know it's natural occurring and that it isn't a fatal flaw, but fairly common. What do you do to deal with it? Thanks, Bruce

Okay, I've seen this answered before, anyone remember how to dissolve the tiny calcium streaks?

I may have to go over to MIMF for this one....

Bruce, there was a discussion some time ago on the AG list. I raided a lab and tried a few different chemicals to get the deposits in suspension -- that worked somewhat.   In the end, a spit coast of shellac worked as well as anything.

I suspect what happens is that the oils and color from the wood itself get drawn out by the alcohol and stain the deposits enough so that they're much less obtrusive.

So if they're not too bad, I'd count on shellac.

Lemon juice on a q-tip or tooth pick bruch

If it's calcium (which I somehow doubt) then vinegar /lemon juice will take it off.

Colin

_________________
I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Hi Bruce,

I remember seeing a discussion of this problem. I paid extra special close attention because I have some beautiful quartersawn mahogany with white deposits all over. Muriatic acid was recommended, with a cautionary note about what it might do to the color of the wood. I haven't tried it yet but when I do I'll test it on a piece of scrap. Let us know what works and what doesn't!

Best wishes,
Viv

Your right Colin, you do want to neutralize after you use Lemon juice. The pieces IRW have had with these spots did appear to be calcium or some type of sodium deposits. I see it a lot in Iron wood that I build jewelry boxes from.

I think it's safer to say that it is some kind of salt exudant. Calcium doesn't play a significant part in plant physiology, sodium does in water transportation. So first off I'd just try wiping down with distilled water.

Colin

_________________
I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Thanks folks, this thread just kept dropping out the bottom before it got a response, I'll see what works.

Bruce, I'd try some denatured on a rag and do what Bob says. I should pull the color out of the wood and stain the deposits.

Okay, the home remedies worked. I was in the kitchen so vinegar was handy. It removed at least 90 percent of the visible streaks which were all small anyway.

Using a toothbrush and scrubbing them with the vinegar removed most of it immediately. So with pore filling and shellacking, I'm sure that nothing will remain. I knew this wasn't a huge deal, but had never dealt with it. Thanks one and all. Just a little care in the final before finishing will be all that is needed.

   This is a natural occuring thing with EIR. I have really don't get worried about it as you need to fill the pores and stain the filler and this takes care of it.
   Sometime alcohol and acetone may get some out but it is still there. It is a mineral deposit and it doesn't allways come out depending on the element involved.
   John Hall

Colin, the mineral we're dealing with is almost certainly calcium carbonate.

I'm not sure how the calcium carbonate would come to exude from EIR unless it's a post harvest environmental contamination. I'll check out my stash of EIR and if I have any exudant I'll take it to work and have one of my post grads analyse it.

Colin

_________________
I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I'm neither a botanist nor a chemist, but the calcium is not being incorporated into sugars as part of photosysthesis (therefore, not extruded in any way), it is probably being shunted into interstitial spaces between cells because the moisture drawn in from nearby soil is likely rich in these minerals. Just a guess.

Tums?