Thread: Blue Spotted Coticule

While digging through my honing paraphernalia that I haven't used in awhile I noticed one of my coticules has developed blue spots that I haven't seen before. My first thought was that maybe something was on the surface so I lapped it and the spots didn't go anywhere. Its weird cause in the spots with no dots there isn't any color change. I think if I lap enough off I can get rid of them, but since they don't seem to affect honing and they kind of look cool I will leave them for now. The slurry stone developed brown spots that lapped off. Not sure what could cause the blue spots, but I read that La Grosse Blanche coticules can develope brown spots so maybe that is what the slurry stone is. The coticule was sitting in a plastic container dry. Hard to see the blue color in the close up photo. I was hoping maybe someone would know what could have caused them or maybe if there is a coticule layer that develops the spots or even if someone has seen something like it before?

This is very dangerous and may be radioactive ....... I am the only authorized blue spot coticule repository in the USA. PM for my address and I will dispose of it safely for a nominal fee .....

Kidding aside, never have seen one like it ..... pretty cool.

Always the possibility of some bacteria having grown from being stored with a slight moisture. I found spots on my Norton stone once after being left in a plastic box for a few months. I would say "smell it" but then I would feel bad if you got some sort of freakish sinus infection!

Well, the only time rocks change color is either through weathering or some rocks change colors because they undergo a chemical change due to environmental factors. I doubt that's your situation so I would assume something settled in there. The question is what?

It's not a natural combination coti/bbw stone is it? I have one that is the opposite of yours - it has yellow spots on the blue side. They are just small yellow layer deposits that became more and more visible as the hone was lapped.

Regards,
Neil

Edit: a layer called La Nouvelle Veine is said to have hazy blue spots. I suspect that is because it is a thick layer that is cut into thinner hones to get the most out of the layer, and presumably the upper/lower cuts have some BBW inclusions.

You didn't store that in my refrigerator did you? Happens to all of my food, there's some cheeses I can't even get home before they start to turn bleu.

Did it eat the pores in the stone? It looks like it in the last picture

The stone is slate backed and it is flat and you can't feel the pores. It almost has a shiny metallic look to it. wish I could get better pictures of it. It was sitting in a plastic tub that I keep alot of my other honing stuff in like stone holders and my other coticule and some other stuff. Most of the rest of my stones I keep in boxes. It didn't even dawn on me that my other coticule is a combo and was sitting on the top of this one for awhile and maybe with the BBW on top might have caused it. I thought coticules were non porous though. I was thinking maybe it was like some that will change color in sunlight. Thanks for all the info.

Originally Posted by thebigspendur

I would assume something settled in there. The question is what?

Rock Lobster.

I'd just use it.