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More chestnut -- and silica question

Joined
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I picked up another hunk of chestnut today, should get 4 bowls out of it. I've read that Chestnut has a lot of tannin in it, which explains how black it gets from a weathered nail. Does it normally have a lot of silica? The first piece I turned was loaded with sparkles that I assume were silica. Can these little monsters create sanding problems?
 
that is what is called a design opportunity......there are standard variations......will look forward to your to see your take....outside the box
 
The first piece I turned was loaded with sparkles that I assume were silica.

Were the sparkles in the endgrain, perhaps in the pores? If so, they might be tyloses, common in white oak, chestnut, osage orange, and other species. The tyloses can look sparkly, especially under a magnifying glass. They tend to seal up the pores.

If the side grain sparkles too, I don't know. I once cut some thick 100+ year old walnut (a mantel from an old house) and it wasn't sparkly but it dulled a brand new Starrett bandsaw bimetal blade with less than 2' of cut. I assumed it was silica in the wood but I didn't examine it further. I still have the wood if anyone wants it!

JKJ
 
Were the sparkles in the endgrain, perhaps in the pores? If so, they might be tyloses, common in white oak, chestnut, osage orange, and other species. The tyloses can look sparkly, especially under a magnifying glass. They tend to seal up the pores.

If the side grain sparkles too, I don't know. I once cut some thick 100+ year old walnut (a mantel from an old house) and it wasn't sparkly but it dulled a brand new Starrett bandsaw bimetal blade with less than 2' of cut. I assumed it was silica in the wood but I didn't examine it further. I still have the wood if anyone wants it!

JKJ

It is mostly in end-grain, perhaps all, I'll take another look. I sat myself down in the sunshine this morning and hand-sanded the darned thing....uhhh, the lovely wood. The sun really brought this sparklies to my attention, so I'll look up tyloses and find out what they're all about. Thanks!
 
Parenchyma cells

Well, if they are tyloses, that explains why I didn't have to sharpen any more often than with the other hard wood I turned recently, Madrona. Tyloses are simply an outgrowth of parenchyma cells, which I assume aren't abrasive.
 
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