Effetre Copper Green (219) is a medium teal/turquoise opaque glass. It's handpulled and can be on the shocky side, but I don't mind that so much in light of all it's other traits. It's sort of unbelievable that I am only just now posting test beads for this colour, but it's been included in every test set I've ever posted so I guess it makes sense that I just lost track of not having done it yet.
I love Copper Green. Mostly I love the colour of it, but I also think it is a pleasantly reactive and versatile colour. I love it so much that I wrote a poem about it on my lunch break one day back in 2009 while at work. That poem won me a box of random glass from Frantz Art Glass, because, I guess, Mike was looking for the corniest possible entry to his poetry contest.
An Ode To Copper Green
In rod form I love you and can't get enough,
It's when I cremate you the going gets tough.
Your colour is tricky and goes all askew
Transforming from green into two shades of blue
With some shades you develop a big, thick black line,
But with purple, the line looks a lot more like wine.
Under clear, you turn yellow! Why is that, o Green?
When you get too hot there's an odd silver sheen...
You spark and you pit and you hate to be hot,
But in spite of all that I still love you a lot.
I'm such a nerd.
Anyway, Copper Green is both awesome and irritating. It's very reactive, and it develops a yucky grey patina on its surface from its high copper content. I don't really believe anymore that the sheen that develops on Copper Green is related to the level of heat. I've found that using Copper Green in combination with some colours limits its ability to develop this patina, but when it's used alone it invariably develops it. I'd give examples of the colours that it hasn't sheened up with but unfortunately I haven't been tracking that information very closely and am disinclined to read through all of my past blog entries to figure it out. I'm basically taking a "lazy pass" here. You can do that, if you want :) Where I've observed it, I have generally mentioned it.
I also used to think that the reason I got so much grey yuckiness on my Copper Green was because I was using a Minor with a 5L concentrator and my flame was probably a bit on the reducing side, but was disabused of that notion when I upgraded my oxycon to a 10L and the sheen kept coming. It's just what Copper Green does.
Once it has sheened up with that greyish muckiness, you have a few options. You can decide that the greyish sheen is a feature rather than a bug and go with the army grey-green-ness of it, you can soak the bead in toilet bowl cleaner, Coca Cola, CLR, pickling solution or some other chemical compound to try to get rid of it (with varying degrees of success), or you can etch it off of the surface of the bead with etching solution or by tumbling it with silicon carbide grit. I generally go for the tumble-etching option because I love the finish I get on my tumble-etched beads and it always, always works.
Here you can see that I got the yucky grey sheen even on the bead I did not reduce. I use a 10L concentrator on a Nortel Minor and my flame was not in any way a reducing one. In the bead that I did reduce, the sheen is a good deal more pronounced and some red patina developed from the copper in the glass coming to the surface.
Silver on top of Copper Green takes on a greyish appearance and gives the glass surface an interestingly aged appearance. When the silver is reduced and encased, it turns yellow. This yellowing is consistent with results I've gotten on other turquoise/teal colours. (e.g. CiM Celadon, Reichenbach Pastel Blue)
Copper Green is an average base for silver glass. It doesn't offer a lot of contrast for the reducing silver glasses, but it doesn't impede their natural beauty in any way. With my TerraNova2 frit, I got an interesting halo effect around the fritty bits and some slow starts to the striking sequence. Probably I could make the frit bloom on this colour with some effort, but there was no magic here.
- Copper Green forms a light halo around Tuxedo dots and lines. On top of Tuxedo, Copper Green separates but develps a strong greyish sheen so the effect is somewhat disguised. Etching would fix that.
- Opal Yellow separates on top of Copper Green.
- Ivory and Copper Green develop a reciprocal dark line reaction.
- Peace separates on top of Copper Green.
Here are some beads made with Copper Green: