Herb are you ready to tackle this lantern with your copper slag?
You posted this link in the Japanese Garden Group a while back and I fell in lust with it.
I have enough skill to make a stab at the wood and glass portion but that black mushroom top might be a bit more challenging.

I'm just finishing up a lantern I started many months ago.
It's a tufa copy of a freform stone lantern I saw on the web.
I'll post a picture soon.

Here is a link that might be useful: Wood glass black lantern to die for.

tufaenough - I can't imagine any way I could copy any part of that lantern. The light box part reminds me of a fine Carriage Clock and as for the roof I don't know what the roof's made of: it looks rather like something produced by a skilled glass blower!

Herb, as I see the different mixes, the cement ratio to the other ingredients is 1:3, 1:4.3 , 1:3. How long was the time to set , how hard was each after demolding ?
I like them all.

Andrea

kobold -

Those with the 1:3 ratio were demoulded about 20 hours after filling the molds - and they were moderately hard, but I could still roughen their surfaces with a knife and a small wire brush (about the size of a toothbrush).

The 1: 4 1/3 ratio one was demolded (I think) 2 days after filling the mold - and very carefully too. After that it was immersed in water for another day. It was about a week before I'd describe it as having hardened somewhat. Now it's gone about another week and feels reasonably hard when I tap it with a fingernail. It's become noticeably lighter in weight too - I guess the peat moss takes some time to dry out.

Herb

Hi Herb.
I think a person might get close using silica fume, black sand, black pigment, grey Portlands.
Maybe even a black stain after that to get that cool flat black look. Of course that cap might be shiny black. Cameras can miss that.

Carving the shape would be a challenge but doable.
I don't think it's something you would want to try to mold.:)

Herb if you were wondering about a pure slag recipe in a different color here is my favorite so far.
This is my best blue so far.
This recipe is 1 part white potland's to 3 parts copper slag and 5% blue pigment and admix.
Very strong concrete.

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So what do you thing of a big blue lantern Herb. big evil grin on my face while asking...

I've seen lanterns in blue/grey granite but not that blue! Who knows - it might catch on with avant-garde Japanese gardeners?

You mention its being 5% blue pigment - what sort of pigment was it - where do you buy pigments like that? I assume they aren't water soluble?

Hi Herb Steeles will sell you a 7 pound bag for around $50.
That is the only place I've seen it.
That is 3-5 time more expensive than other colors.
It's just the same as any other dry pigment but nasty if you let it get in the air. It settles on everything and instantly stains them blue if they get wet.
It's the worst color for this.

This blue is the closest I can get to that fine cobalt blue in pottery.
It's the shiny black slag that tricks you into thinking the blue is dark.

What about if I do my pagoda lantern in bright yellow, bright blue, and bright green.:)
But actually I'm going for simple dark gray for that lantern.

I'd love to see the blue, but am getting the dreaded ? sign. Tufaenough can you re-post?

Mabel

Hi Mabel
This odd ball pot is cured but I have it leaching in the rain full of water so it is darker than it would be dry.:)
The rain never stops this spring.
The broken chip in front is a dry piece of virtually the same blue.
The pot is the same recipe except 25% more blue pigment.
1 portlands white, 3 copper slag, 8-9% blue pigment.
Bone dry I expect it to be a bit darker blue than the broken chip.

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