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Beware: Opaline Overdose

Maybe the only thing better than a misty morning is a misty morning with a knock-your-socks off sunrise.

We had one of those last week, while I was still rhapsodizing about Opaline.  I’m just so psyched about this glass that I’m having a hard time keeping my enthusiasm in check.


Not only can Opaline work like a gauzy filter over other colors (at my age one can’t say enough good things about gauzy filters), but in a thicker section, it has an internal fire not unlike certain colorations of an Oregon sunrise.


OK, OK…a cold shower of elementary glass chemistry usually works to snap me out of this kind of delirium.

What makes this glass so different than a standard white opal?

Opalescent glasses are typically made with fluorine, hence called fluorine opals. The fluorine exists as a minute crystalline (i.e. non-glass) particle suspended within the glass matrix.

This new Opaline, on the other hand, is a phosphate opal. Unlike fluorine, the phosphate particle is a glass – i.e., a glass suspended within a glass – and as such is more translucent…

…and fiery….and diaphanous….and romantic….and elegiac….and may lead to excessive blathering if handled without gloves.

31 Responses to Beware: Opaline Overdose

  1. It is beautiful… I’m really looking forward to trying it out!

  2. Oh my insides are burning and yearning.

  3. chaniarts says:

    that really does look like a real opal, hence the name?

  4. So, in the “opalescent” case you have an amorphous mix (the “glass”) with fluride (“ide”) scattered around. Since hexafluorosilicate is used in porcelain, which is kind of opaque, is that the magic?

    But with “opaline” we have the phosphate (in the form of calcium silica phosphate??) as semi-transparent (rather than opaque) blebs…that look like they bond with the glass. See: (

    What it looks like you’ve ended up with is what we rock geeks would call “potch opal”, that is, opal without the “flash” of color, but still with the hazy amber shade you see in the background of “precious” opal. Now, if you could come up with something that looks like a good hunk of Lightning Ridge in sheet form for under $1000US a sheet, I’ll be camping out at the door for the first sheet!

    In any case… I love the stuff.

  5. Lani says:

    geekgeekgeekgeekgeekgeek. Stoppit, Gary!

  6. Lani says:

    Carrie, I actually thought of your work when I first saw this stuff.

    Les, Pepto helps.

    Chani, YEP!

  7. Geez, I guess you’re not one of THOSE gals, eh? I mean, when I talk geek with The Dot (especially when I say it in Klingon!) she gets all mushy and everything.

    And what’s this… TWO logins? “lani” and “lmcrgregor”?

    In any case… it does look like a sunset (or sunrise) trapped in glass. I just got to get my hands on some of it…

  8. Lani says:

    Hmmmmm. I hadn’t even noticed the schizo login. Thanx, Alice.

  9. OH I think only Opaline will help!!!!! Les

  10. Toni says:

    The BE winter sale is still going on, isn’t it, Lani? Maybe I drive on over Saturday and pick up a couple of sheets. I need some powder anyway…Starting my shopping list now.

  11. Mary Kay says:

    Hi Toni,

    The Bullseye Resource Center sale (walk-in only) goes through Saturday, and we have just added a White Sale–spend $200 or more on Friday or Saturday and get a free full sheet of White Opal or White Opaque curious fusible glass (while supplies last). Details are forthcoming in an email later today.

    Mary Kay

  12. Lani says:

    A White Sale???? My blog’s been co-opted by Macys???? MK, how’d you get in here?

  13. Mary Kay says:

    Didn’t know I was a hacker, did you?


  14. Toni says:

    Thanks for the info, Mary Kay! I looove white sales. ;)

  15. Hey… Mary Kay… I don’t have your email. Could you pop me a copy of your email? I’m going to send Cynthia over there with my credit card number. Make sure she doesn’t take all of you out to lunch, eh?

  16. Mary Kay says:


    Can do. You should have an email from me now.


  17. jenn says:

    gary- why don’t you wanna take all those hardworking peeps to lunch?

  18. Because I can’t be there with them to watch their innocent little faces light up with joy at the thought of Free Grub. Uh-Oh… guess I’m going to be buying pizza for the guys next time I’m out in Portland. “Please, sir, may I have some more?”

  19. Mary Kay says:

    Mmm, linguica, mushrooms and green peppers…

  20. “linguica, mushrooms and green peppers”…sounds like the color mix for one of the “streakies”. Cap it w/ opaline and BINGO!

  21. Hmmmm! is this exceptional glass going to be available in CASTING billets!!! wish list! dream list! Les

  22. OK. The above explains all those random pizza comments I heard today at the RC.

    You know, most opalines I’ve seen have a cold/blue cast. What’s interesting about THIS one is that in thicker chunks it appears warmish. I hefted the stepped block sample in the RC today, held it up to the light and saw pale, pale apricot. Figured it was the lighting and took the block outside. Apricot, and it cools off when it gets thinner)

    (In the world of me this is a very good thing)

    Depending on how this reacts with, say, ruby striker, coral and amber tints, you may have just shipped a perfect carrier glass for shading fleshtones. Cut fine opaline FRIT (hint, hint) with 1401 fine and tuck it under a thin layer of coral powder…

    And I can always sheathe it in juniper to bring it back to neutral… ;-) Hmmmm.

  23. Does anyone in Victoria, Australia have it yet though?

  24. Lani says:

    Dunno, Peter, I’ll check on Monday.

  25. Lani says:

    Les, no the Opaline won’t be available as a billet until we’ve done more testing. Right now, it appears that it will go too opaque in a really long soak (like 12 hours up at 1550 – or schedules typical of long reservoir castings/soaks) – which is how most billets are used.
    Right now the Opaline sheet keeps its color (i.e., translucency) at the standard fuse test, which is 1500F for 10 minutes. That’s our standard test cycle. Beyond that, you’d need to test for your own conditions.

  26. Thankyou Lani! Experiment ! Experiement will be my excitement with this new glass. Interesting to see after the 3rd firing at 1480 for 30 min. what it will do as I am going up alot slower now than I used to( with the Squeeze hold as well,) and find I am getting really nice movement still. (instead of how I used to go to 1550 and hold 1 hour. ) This will be good for this glass as you mention. Les

  27. Inspiration anyone?? I’ve got something else in mind to try but these are beautiful.

  28. Due to arrive here anyday now.I’ve got several ideas and a few questions.

  29. I’ve put a small piece through, and it really is beautiful.Your photo of sunrise is apt.Not sure how to get the most out of it, I may use it without added colour.

  30. barbara says:

    Has anyone found opaline striker sheet to be reactive with turquoise? I have a dark, dark brown outcome that I’m attempting to retire right now to a higher temp to see what I’ve done wrong! Reaction or me?

  31. barbara says:


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