Tool marks or just the wood?

[Stigmorgan]

So I've started working on a piece of my dry cherry wood (the green stuff I've got needs to wait a while as the first bowl I did from it has gone the way of the banana) I've sanded it back quite a lot but there are some whitish marks and patches that I cant seem to sand out and I'm not sure if they are a result of maybe the tool not being sharp enough or if its just the way the wood has grown.

The pics and vid are after I turned it from the worm screw to the tenon, I rounded it off on the wormscrew and sanded it on the tenon, would love your c&c.

Here a shot of my cherry banana I expected it to move a little but didn't think it would be quite so much as I expected the wax finish would help hold onto the moisture, unfortunately there's not enough thickness in the base of this one to put it back on the lathe and fully flatten it back out.

 

[peter-harrison]

I am sure those are tool marks. Sadly, it takes a LOT of sanding to get out those kinds of mark in end grain (yes, I am the kind of wood turner who uses a lot of sandpaper!) If you've got one of those foam disc sanders to put in an electric drill, it will speed it up a lot.

 

[Tris]

Sometimes get this, it looks like tiny bits of end grain are being plucked out rather than cut. Give it a coat of sanding sealer then a very light cut with a freshly sharpened tool.