Questions On Opals

[pwsg07]

1. Which opal mine yields stable or non-crazing opal? I know Welo opal will not craze

2. What are the characteristics of the opals from Indonesia, Honduras, and Brazil? I don't know much information of opals from this source except that Indonesia yields black opals.

3. Any updated information or books I can learn more about opals?

4. What are the rarer or better qualities of Welo opals? Which body colour, transparency, patterns of the play of colour is rarer?

5. Does any one have Welo opals that craze? I have a piece of opal specimen from Ethiopia and it crazes so much. I was told the stone is from a different mine. The seller didn't specify the mine.

 

[Seaglow]

1. Which opal mine yields stable or non-crazing opal? I know Welo opal will not craze

2. What are the characteristics of the opals from Indonesia, Honduras, and Brazil? I don't know much information of opals from this source except that Indonesia yields black opals.

3. Any updated information or books I can learn more about opals?

4. What are the rarer or better qualities of Welo opals? Which body colour, transparency, patterns of the play of colour is rarer?

5. Does any one have Welo opals that craze? I have a piece of opal specimen from Ethiopia and it crazes so much. I was told the stone is from a different mine. The seller didn't specify the mine.

When you say it crazes so much it means that it was good when you got it and it crazed?

Sometimes they may not be crazing but cracked either when banged or cut because of pressure.

Australian may tend to craze with time, but black opals are usually more stable than their white counterparts based on old materials I've seen.

Ethiopians are good, but I've seen cracked materials.

Mexican are also good. Some Indonesian and US opals can be unstable. Not sure from other locations.

For unstable opals, they can be treated with opticon or other stabilizers.

For Welo, the black/dark brown/dark grays are rarer, and the landscape opals with nice "fossil" inclusions doesn't come by often. A collectible is also one that has potch with a honeycomb pattern. The big flashes are prettiest and red the nicest with a combo of blue or purple, IMO.

 

[pwsg07]

When you say it crazes so much it means that it was good when you got it and it crazed?

Sometimes they may not be crazing but cracked either when banged or cut because of pressure.

Australian may tend to craze with time, but black opals are usually more stable than their white counterparts based on old materials I've seen.

Ethiopians are good, but I've seen cracked materials.

Mexican are also good. Some Indonesian and US opals can be unstable. Not sure from other locations.

For unstable opals, they can be treated with opticon or other stabilizers.

For Welo, the black/dark brown/dark grays are rarer, and the landscape opals with nice "fossil" inclusions doesn't come by often. A collectible is also one that has potch with a honeycomb pattern. The big flashes are prettiest and red the nicest with a combo of blue or purple, IMO.

Thank you for sharing, Seaglow.

It is a rough specimen from wello. It is crystal clear amber coloured. When I received it, it has some cracks or craze. Since it is transparent, I can see the other side of the stone from one side. But after a long time, I looked at it again. it crazed so much I hardly see the other size from one side. Since I have bad memory and I didn't take any photo, I cannot remember how much it craze. I am quite sure it craze more after I received it. There is no dropping or cut. The only thing I have done is washing it with water. I though the rough are kind of dirty so I rinse it with water. I don't want any unwanted bug coming with it.

I bought this rough because I thought I can cut this piece of rough and it is huge. Since it has so many cracks internally, it cannot be cut. It only stays in my room. My room is facing east and gets very hot during the day. Even I have air conditioner, my room is still very hot. Maybe the temperature and the air conditioning take away the moisture of the rough? I have other opals from the same dealer but they are not crazing. Those one are cabs.

I have not much information about the opals from Indonesia, Honduras, and Brazil. Sometimes, I saw some nice one for sell from Indonesia. I am not sure how stable the opals so I never buy any.

The characteristic I observed from Australian opals is that they usually have the play of colour on one side. While those Ethiopian opals always shows the play of colour on both sides. The Mexican one always highly transparent.

The dealer told me only Ethiopian opals shows honeycomb patterns and I think the honeycomb always has brighter fire than other patterns. She also told me the black and contra luz opals are usually not stable. The other dealer told me colorless Ethiopian opals are rarer. Now I am looking for colourless/ water clear Ethiopian opals. I have seen a Ethiopian black opal at the gem show today. it is transparent when I shine the light through it. I don't see black opals very much and I thought they are opaque?

I have seen the videos of the crystal opals on the black opal direct. They don't seem to have the transparency of the Mexican opals and they are called crystal opals?

Have you started your GG class? Where are you taking your class? I took mine long time ago in NYC. The instructor are more knowledgeable in diamonds than in coloured stones.

 

[Seaglow]

Thank you for sharing, Seaglow.

It is a rough specimen from wello. It is crystal clear amber coloured. When I received it, it has some cracks or craze. Since it is transparent, I can see the other side of the stone from one side. But after a long time, I looked at it again. it crazed so much I hardly see the other size from one side. Since I have bad memory and I didn't take any photo, I cannot remember how much it craze. I am quite sure it craze more after I received it. There is no dropping or cut. The only thing I have done is washing it with water. I though the rough are kind of dirty so I rinse it with water. I don't want any unwanted bug coming with it.

I bought this rough because I thought I can cut this piece of rough and it is huge. Since it has so many cracks internally, it cannot be cut. It only stays in my room. My room is facing east and gets very hot during the day. Even I have air conditioner, my room is still very hot. Maybe the temperature and the air conditioning take away the moisture of the rough? I have other opals from the same dealer but they are not crazing. Those one are cabs.

I have not much information about the opals from Indonesia, Honduras, and Brazil. Sometimes, I saw some nice one for sell from Indonesia. I am not sure how stable the opals so I never buy any.

The characteristic I observed from Australian opals is that they usually have the play of colour on one side. While those Ethiopian opals always shows the play of colour on both sides. The Mexican one always highly transparent.

The dealer told me only Ethiopian opals shows honeycomb patterns and I think the honeycomb always has brighter fire than other patterns. She also told me the black and contra luz opals are usually not stable. The other dealer told me colorless Ethiopian opals are rarer. Now I am looking for colourless/ water clear Ethiopian opals. I have seen a Ethiopian black opal at the gem show today. it is transparent when I shine the light through it. I don't see black opals very much and I thought they are opaque?

I have seen the videos of the crystal opals on the black opal direct. They don't seem to have the transparency of the Mexican opals and they are called crystal opals?

Have you started your GG class? Where are you taking your class? I took mine long time ago in NYC. The instructor are more knowledgeable in diamonds than in coloured stones.

Must be from crazing. I heard (not from personal experience) that Honduran can be unstable. Ethiopians are more 3D than Australians, and yes, black can have some transparency in Ethiopians but be careful of dyed/irradiated. The rare ones I talk of are natural colored. The clear ones are rare but the display of colors I find better in the honey colored and darker colors.

I start my GG class in a couple of months.