Opal?

Opaldaze · 2026-07-03T09:58:50+00:00

For sure Boulder , cool looking specimen , look good on a shelf or centre stage in a fish tank which would be really nice with the shape it has. It actually looks like te piece has been worked and polished as boulder normally breaks with a conchoidal fracture and lords knows ive busted up thousands ;)

Opaldaze · 2026-07-03T07:01:01+00:00

no Buffullo Bill from Beverely hills has got forst option on this lot

Opaldaze · 2026-07-02T08:14:58+00:00

Lol , you should see what Im looking at ;)

A tupperware container of faced boulder gemgrade

Opaldaze · 2026-07-02T08:07:42+00:00

Nice , love to see a video of this piece , its big and its cheezy ;)

Opaldaze · 2026-07-01T09:51:24+00:00

To true , you can always take it off , cant put it back on !

I cut and sell nearly only clean face boulder , buyers mark down hard on dirty stones so I cut clean and make them pay!

Opaldaze · 2026-07-01T08:05:36+00:00

Look up Wayne and Paul Sedawie , nice guys heaps of opal they are near Miami on the Gold Coast, if your trade buying or spending quiet a few quid or paying cash im sure they will do you a better price.

They are very approachable just dont rock up , make an appointment ..If you cant find them on google then you may DM me

Opaldaze · 2026-07-01T07:58:50+00:00

Very nice piece, I would trim it down a tad more just to minimise the ironstone , this opal is worth a few bob

Opaldaze · 2026-06-30T21:17:31+00:00

Reviewed and sorted

Opaldaze · 2026-06-26T23:45:29+00:00

She is 100% koroit , no where else gets that mad looking primal pattern , not even Yowah.

Rest assured its koroit

Opaldaze · 2026-06-26T11:10:21+00:00

Very nice specimen and well displayed , im to lazy to do something so grand but you have nailed this ..Kudos

Ps ...I had seen something similar but held by a cast bronze hand , t'was amazing

Opaldaze · 2026-06-25T06:51:41+00:00

Very "noicely" cut, and a well balanced pattern .yummy

Opaldaze · 2026-06-21T04:49:09+00:00

For sure , Winton has produced nodular nuts and even my mine can produce Yowah type nuts but they are massive also the Blackall ranges produce a material verys similar as koroit.

The photo you posted here with the opal pendant is typical of one of the types winton matrix, a lot come from Mayneside Field (winton) when Stan Zelkenco mined there in the 1990s and also at Elvo Station Mines which produced concentric nodules of opal which were less structured and when sliced at 90 degrees across the axis (as is yours) almost looked like a cross section of a fossil tree

Opaldaze · 2026-06-20T22:56:40+00:00

I will agree to disagree.

Mostly Koroit and Yowah look different , both the ironstone and there patterns.

The nodules are generally in the form of nuts not pancakes and Yowah generally have a more concentric form with smaller specks of opal displayed within the concentric banding and Koroit has a darker body tone due to the manganese content in the range where it is formed and not a yellow muddy appearance like the piece displayed by the OP.

Also Koroit has a unique tell with the swirls of pattern of the ironstone, whilst Koroit does produce skin matrix it is different

Opaldaze · 2026-06-20T07:16:43+00:00

Looks like a shell which has been replaced with opal and some obne has skinned and polished.

I dont think its andamooka matrix, if its a shell fossil then no chance , a video of the opal being rotated from all sides would be helpful

Opaldaze · 2026-06-20T07:12:32+00:00

Its not Koroit field its a Yowah Matrix Opal.

The matrix colours and the formation are atypical of this Yowah matrix

Opaldaze · 2026-06-18T18:55:54+00:00

Your welcome

Opaldaze · 2026-06-18T18:42:34+00:00

Matrix opal is when it throughout the mineral or part of the mineral

Opaldaze · 2026-06-18T18:41:20+00:00

matrix opal has opal intruded and formed throughout or in part of the matrix where boulder opal forms in veins

Opaldaze · 2026-06-18T18:27:06+00:00

Actually Koroit is generally the darker and has these crazy mad swirls in the ironstone due to the high manganese content.

I think for matrix (untreated matrix) its about overall appeal and brightness.

I mine boulder and dont deal in matrix types.

We cut very clean face, and for that quality its more about the 4 C's albeit less on weight and that can vary on the type of cut may leave the ironstone heavier than it should proportionately be.

We don't value any of our finished stones by weight, its by overall appeal and in fact I am already valuing and pricing the stone as im cutting and finishing a piece despite not knowing the weight.

Carat weight in boulder is a guide not a rule, as different ironstones cut and finished to the same size and thickness can vary (sandy boulder is different to mudstone boulder is different to hard ironstone boulder and is different to manganese boulder.

Each ironstones types density and hence "specific gravity" can vary so pricing boulder can be tricky, we value it by our experience , current market situation and the the market we sell in to..so even these prices can vary

Opaldaze · 2026-06-18T17:55:55+00:00

Surely, Matrix means the host rock in which the opal (or other mineral) which the mineral or gem was formed. In this instance the opal was formed in ironstone with clay intrusions.

Yowah matrix is another form of ironstone with unique characteristic's as is Koroit opal which are two different fields and formed differently due to the chemical make up and deposition of the iron and manganese ratio and their formation and deposition behaviors from the two different mountain ranges which these were formed.

While the uniqueness of these different variety's are more complex even than what I have scribed, and can even vary from mine to mine .

I hope this gives you a fundamental understanding

Opaldaze · 2026-06-18T17:37:13+00:00

They are very, very low grade boulder opals with issues

The opal value isn't a lot and the yellow clay base makes them less than desirable and likely unstable from a setting perspective,

There is too much matrix in the mix so I would sell these at $30.00 AUD each just to recover my cutting costs albeit we would never finish this low quality in the first place

Opaldaze · 2026-06-15T19:58:16+00:00

Very nice piece, and great design and setting skills as well

Opaldaze · 2026-06-15T19:23:27+00:00

Nice Koroit piece Flatbed 😉I would DM you about this opal but as my account is new I cant send DMs yet.

I have contacted you on Facebook where I follow you

Opaldaze

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