Crystalica verus Spruce Pine Batch, Spectrum

[Virginia Wilson]

For those who have had experience with Spruce Pine Batch and Crystalica, how would you compare the two?
Example, workability, compatibility, I know it melts at a lower temperature, how is it on the furnace lining?
What is your dream glass cullet?

[Miles Koester]

I'm assisting a guy using GLASMA this last month. He likes it because he claims he can melt it at lower temps, which offsets the cost difference. Its also truely pellatized, and is substantially less dusty. SP is pellatized only in theory, its so dusty it might as well be powder..

From an outside perspective I don't know why everyone dosent use GLASMA. But i dont own my own shop, and i'm sure plenty of people here could tell you why spruce pine is more popular. I think he may of run into some
Compatibility issues with stiffer colors, but I think it wasnt anything adjusted annealing cycles didn't fix. Workability wise, its hard to tell a difference between it and SP, but sure, its slightly softer, which is saying something, because SP is already very nice.

[Pete VanderLaan]

That's a comparison of apples and oranges. SP is a batch. Cristalica is a cullet.

[Miles Koester]

Oh. I must be confusing Crystalica for whatever the batch from Sweden that comes in beige bags people use, which is called Glasma.

[Pete VanderLaan]

That's GLASMA.

[Miles Koester]

Facepalm. So anyway, why don't more people that are geared for melting batch not using that stuff? Availability?

Originally Posted by Pete VanderLaan

That's GLASMA.

[Pete VanderLaan]

GLASMA stopped making cullet.

[Dan Vanantwerp]

Hi Virginia, I've been using Crystallica cullet now for 1/2 a year or so. I was using Spruce Pine cullet before they stopped making it. The workability seemed just a hair shorter with Crystallica to begin with (couple pieces hit the floor during transfer) but I guess I have adjusted such that I can tell no difference now.

I recently used it to make a silver blue luster. I did not frit the cullet just to see how the funny little squiggles would mix with the chemicals. Seemed to work very well.

I'm no master gaffer, but I really could not imagine a glass could work better for me than Crystallica. I wish it was cheaper, but that just can't be helped...

[Virginia Wilson]

thanks for the input guys! Crystalica appears to be in my future. I am looking forward to using it.

[Scott Novota]

I have used them all.

They all have about the same working time but the C-cullet has a more liner lock up as it cools to me compared to the fast ramp to cool at the end of SP/Spec but that might just be my personal workflow.

C-cullet has a notable brilliance compared to Spectrum/Sp to me. Alas, C-cullet leaves a bit of what I assume to be borax or some derivative of it on my gathering port due to lack of flue. This also seems to be nibbling at the refractory a bit. I am on my 4th year of this furnace so wear and tear is normal but it does seem to have a slightly more corrosive nature to it than SP/Spectrum. Take that with a grain of salt it could just be normal wear and tear accelerating with age of the equipment.

I have melted over 10 tons of the spectrum and about 1/2 that of the SP cullet/batch. About 5 tons of the C-Cullet.

90% sure I will be getting more C-cullet when I run out bar something crazy happening.

[Pete VanderLaan]

I did try to get Dobern to remove the borax from the cullet when I was still involved in that venture and offered up a very easy solution to the perceived problem with corrosion. They passed ,which did not surprise me. In talking to Jim Myers, I am pretty sure he is going to be willing to mix and ship my formulation I did last year when SP thought there would be a lithium shortage. As near as I can see Tom does not want to stock potassium nitrate and I'm not willing to see it mixed with sodium nitrate. A boy has to have pride in his work.

That is one fine batch and is the best I've done in fifty years, but there's no cullet.

[Scott Novota]

Well, I guess storing it in the grill with some sulfur is out of the question.

[Paul Thompson]

Originally Posted by Scott Novota

Well, I guess storing it in the grill with some sulfur is out of the question.

Would a protective layer of magnesium powder help?