Printable View
Purple Slurry = Blue Belgian. Correct? What color slurry does slate make?
I found a 6"x1.5" yellow coticule at the local flea market a few weekends ago. (My first stone.) I thought the backing was regular slate. (It was glued to the yellow.) Yesterday I read about the purple slurry, so I tried rubbing the stone with a small piece of 1000-grit sandpaper. The slurry came quick and purple. In less than three seconds, I had a nice purple slurry.
So is this a definitive test?
Thanks,
Christopher
Short answer, I'm going to say yes.
The other thing you'll notice about Belgian Blue stone that you won't on the slate backing after you lap the layer of age/dirt/grime, etc off the stone is that the blue stone is more visually unique than slate which on all slate backed coticules I've seen is uniform.
Check out some close ups of the Belgian Blue HERE
I don't think you'd ever see slate look like that. Does that help you confirm your stone?
Chris L
I'm going to say yes as well, coz I bought a blue/yellow combo, which is the one now in bits for sale as slurry stones. The blue is actually a deep purple, looks quite cool.
Yep.
And slate slurry is black / grey. Definitely not purple.
I agree .. my blue coticule produces a lovely purple colored slurry
:)
I saw that thread. My stone has the little inclusions too. But since I've never looked close at slate and don't have any on hand, I didn't know if slate has them too.Quote:
Originally Posted by Chrisl
I'll try to snap a photo tonight.
Thanks,
Christopher
Do all of you have small blue bouts to build the "purple" slurry on the "main" belgian blue stone?
The "cotigura" I have doesn't have the blue stone on the other side, it's only plain grey slate...
I don't use the belgian blue with slurry, I only use water. :shrug:
I never knew you guys used a small blue bout to raise slurry on the blue.
Live and learn.
Woohoo! It's a Blue Belgian. My vintage stone is a combo! (And all for $20 at the local flea market.)Quote:
Originally Posted by Chrisl
And it has plenty of the little red garnets too! (See photos.)
Me =)
The large majority of us that own the blue stone do NOT use blue bouts to form blue slurry. The large majority of blue stone owners use water just like you do. Why? You can't buy blue bouts, you can't normally buy combo yellow/blue slurry stones. I really like forming blue slurry on a blue stone for doing cutting/pre-poliishing work. Old_School recently cut up a natural combo into slurry stones. Earlier this year, I had Howard Schechter cut up an 8"x3" Blue stone into 1/2" by 3" blue slurry stones. And to my knowledge, prior to that I think only Randy Tuttle cut up a blue stone? The supply for such blue slurry stones is almost nil. I think it's because the demand for them is just a hair more than nil.:shrug:Quote:
Originally Posted by Leon
I do have ONE extra 1/2"x3" Belgian Blue slurry stone left. I'd sell it to the first PM'er for $15 including shipping or Intl $12 + whatever actual shipping charge would be.
You my friend, have totally scored! Nice combo stone! You'll be very very happy with it. Plus, with the crisp dividing line, in the pics it looks to me like you have a non-natural combo; these have not been produced for IIRC 50+ years? Isn't it cool to find vintage stones and lap away the grime and bring back their beauty? It's one of my favorite things to do; too bad it doesn't happen more often for me (then maybe it wouldn't be as special)!Quote:
Originally Posted by CJBianco
Chris L
Mine wasn't a natural combo, rather a glued one. A real shame about it's demise, but at least a few members are able to give it new life.Quote:
Originally Posted by Chrisl
And I bought one. It's in the mail. =)Quote:
Originally Posted by Chrisl
Yep. It's glued. A non-natural combo, but a combo nonetheless.Quote:
You my friend, have totally scored! Nice combo stone! You'll be very very happy with it...in the pics it looks to me like you have a non-natural combo; these have not been produced for IIRC 50+ years?
Thanks, everyone. =)
Me
Slate makes a dark gray slurry and the blue makes a purple slurry. That property is called "streak" to geologists and is one of the field tests used to identify stones. They rub the stone against a little pad of sand paper or a ceramic plate and the true color comes out and that's the "streak".
Howard
Ardennes Coticule uses slate to back their coticules, but the old coticule producers used Belgian Blue stone. After all it was plenty available. Ardennes doesn't do that anymore, because it is much more cost-effective to glue to, foreign produced, slate flooring tiles. (Labor costs have exploded since the old days). Anyway, almost all vintage coticules are glued to a blue stone, while Ardennes' coticules are backed to slate, unless they don't need to glue it, in the case the blue is naturally bonded to the yellow.
Bart.