Testing new gemstones and others

If I am trying out a new material to add to metal clay, I will test fire it alone before I add it to my clay to see if it can withstand my normal firing temperature.

BeadFX just got in new gemstones and I have a sampling of six of them which I am test firing. The new stone that I am testing are:

• Garnet CZ (3mm round)
• Lab created Black Saphire (7mm round)
• Aqua CZ (3mm round) -this might be my favorite imagine it in silver
  
• Lab created blue Spinel (10mm heart)
• Lavender CZ (3mm)
• Lab created ruby (3mm)

I decide the the first test to subject them to is my maximum (the logic here is two things one according to some of the research I have made they should survive and the other point is if they all survive then no need to test them any further, thankfully I have extras if any fail)

The result of the first firing at 1650F for 2 hours (the stones on the LEFT are the ones that have been fired the stones on the RIGHT are the unfired samples) :

Garnet CZ (no obvious change in colour)



Lab created Black Saphire (no obvious change in colour)




Aqua CZ (Oh, Oh BIG CHANGE!!!)

Lavender CZ (no obvious change)

Lab created Blue Spinel (no obvious change)

Lab created Ruby (no obvious change)

After the first tests all but the aqua cz survived 1650F for 2 hours. Now I will have to retest aqua at a lower temperature. It seems that greens tend to be the least reliable colours so the fact that the aqua failed this test stands to reason . I will now test a new aqua cz at 1200F and see what happens.

Of note in my reading I have seen note that black saphires are not always consistent. I have had luck with these ones but it is interesting to note and it is only one test.

Lastly,

On my last post of adding gemstones I had made mention of my experiments with firing Labradorite at 1650F. Here is a picture of what happened:

I will update you on the successes or failures with the aqua CZ's.