Labradorite

Prospecting Australia

Help Support Prospecting Australia:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

headbut

Paul
Joined
May 13, 2013
Messages
1,444
Reaction score
232
Location
Sydney, NSW
Hi Guys , got this in my tumbling rock lot & noticed this rainbow affect inside, well when its wet, it looks stunning inside, any ideas what this is ?
1373722624_photo1.jpg

1373722742_photo2.jpg

1373722815_photo3.jpg

1373722865_photo4.jpg

1373722908_photo.jpg
 
Cool rock headbut, first and last pic look sort of like Opal, specific gravity test for that 1 I think. Opal is 2.1 and Zircon is 4.5. I was reading on DIGS the other day that there are opal deposits near Sydney, not gem quality but still here.

Will be interested to see what the more experienced members say.
 
My guess is quartz, I have seen this rainbow effect in some bits before. A bit hard to tell from a photo though.

DD
 
Heatho said:
Cool rock headbut, first and last pic look sort of like Opal, specific gravity test for that 1 I think. Opal is 2.1 and Zircon is 4.5. I was reading on DIGS the other day that there are opal deposits near Sydney, not gem quality but still here.

Will be interested to see what the more experienced members say.

G'day guys,

I know a little bit about the opal finds around the Sydney area Heatho. My father used to shoot rabbits on a property out near Mandurama (South of Bathurst and not far from Neville) called Sunny Corner back in the fifties and there was an old section down behind the property called Rocky Bridge Creek. That was Australia's first opal discovery and subsequent mine. It's just a bit of a tunnel on the side of a hill going into an ancient Basalt layer that had quite a bit of Amber coloured opal of small vug and nodule types.

It would have to have been found and worked pre 1880's as we had our first opal found in the 1890's here. I think White Cliffs may have been the first major opal field if I recall correctly.

headbut17: Not real sure of the rock type Paul? Looks pretty good though! That opalescence is very intriguing. I hope you track down your answer.

All the best,
Shauno.
 
Syndyne said:
Heatho said:
Cool rock headbut, first and last pic look sort of like Opal, specific gravity test for that 1 I think. Opal is 2.1 and Zircon is 4.5. I was reading on DIGS the other day that there are opal deposits near Sydney, not gem quality but still here.

Will be interested to see what the more experienced members say.

G'day guys,

I know a little bit about the opal finds around the Sydney area Heatho. My father used to shoot rabbits on a property out near Mandurama (South of Bathurst and not far from Neville) called Sunny Corner back in the fifties and there was an old section down behind the property called Rocky Bridge Creek. That was Australia's first opal discovery and subsequent mine. It's just a bit of a tunnel on the side of a hill going into an ancient Basalt layer that had quite a bit of Amber coloured opal of small vug and nodule types.

It would have to have been found and worked pre 1880's as we had our first opal found in the 1890's here. I think White Cliffs may have been the first major opal field if I recall correctly.

headbut17: Not real sure of the rock type Paul? Looks pretty good though! That opalescence is very intriguing. I hope you track down your answer.

All the best,
Shauno.

Awesome info Shauno, that Sunny Corner really is an interesting place, I've been there a few times, never knew of the Opal there though. The deposit I read about is near Brooklyn at the mouth of the Hawkesbury under sandstone overhangs. This forum is great.

I agree with you guys after looking at Labradorite pics.
 
Heatho said:
Awesome info Shauno, that Sunny Corner really is an interesting place, I've been there a few times, never knew of the Opal there though. The deposit I read about is near Brooklyn at the mouth of the Hawkesbury under sandstone overhangs. This forum is great.

I agree with you guys after looking at Labradorite pics.

My pleasure Heatho.

Sunny Corner is just the old property title name. It was well hidden away in the hills out in the middle of nowhere. It's not affiliated with the actual Sunny Corner area North of Lithgow and Bathurst. I'll see if the old man can locate it on Google Earth and I can put up a small thread on the topic :)


headbut17 said:
Thanks Guys , I agree when looking at Labrodorite , it looks exactly like my rock :)

Glad the guys pointed you in the right direction Paul! Nicely done to all here.
Kindest regards,
Shauno.
 
Awesome info Shauno, that Sunny Corner really is an interesting place, I've been there a few times, never knew of the Opal there though. The deposit I read about is near Brooklyn at the mouth of the Hawkesbury under sandstone overhangs. This forum is great.

I agree with you guys after looking at Labradorite pics.
Would love some more info on this
 
Awesome info Shauno, that Sunny Corner really is an interesting place, I've been there a few times, never knew of the Opal there though. The deposit I read about is near Brooklyn at the mouth of the Hawkesbury under sandstone overhangs. This forum is great.

I agree with you guys after looking at Labradorite pics.
Would love more info on the brooklyn deposit, also I would like to check out this location at rocky bridge Creek I believe I have the close coordinates to the first opal mine they had there
 
It could be labradorite but it needs more info. The clue is how a lump of it breaks. Does it break along a series of stepped cleavage planes (labradorite)? Or along curved surfaces much as glass fractures (opal)? Looking at a polished surface tells little.

Labradorite tends to break along planar surfaces that intersect at 86 and 94 degrees (almost at right-angles) because it is a feldspar (the plagioclase feldspar anorthite). It displays schiller structure, caused by huge numbers of parallel inclusions of some other mineral. giving it colour change as you move it.


1659660349661.png 1659660632891.png


Opal breaks along curved surfaces. Its color variation is caused by layers of silica spheres of differing sizes. which break up light like prisms as you move it.

1659660458994.png1659660747256.png

The way the colour is distributed in labradorite is usually a bit different. Usually broader areas of colour with more diffuse boundaries to each colour not abrupt boundaries.

1659661113588.png

Labradorite is almost always in the rock gabbro and makes up a major part of the rock (e.g. 75% plus). Opal can occur in various rocks, but usually as thin seams or vug-fillings.
 
Last edited:

Latest posts

Top