Polishing a 250 carat Ethiopian Opal

This 8 minute long video shows the entire process of polishing a rough 250 chunk of opal from start to finish. This includes wet grinding on a Diamond Pacific Genie, and Dry final polishing with diamond paste.
Even more importantly, it shows why larger Ethiopian opals are so rare. They are highly prone to cracking during, and after they are polished. This is due to their hydrophane nature; they absorb water. So as they are allowed to dry out, their surface contracts and creates cracks. Much light the surface of a desert as it loses its moisture.
I consider myself a savvy cutter and an honest gem merchant. So I always ensure that any stone I sell is totally stable before It goes on the market. This video illustrates why. And also why you should always ask a stone seller how long ago a stone was cut. If cut very recently, it may be worth it to wait. Instead of placing that burden on my customers, I take the burden and risk of waiting for a stone to stabilize before I sell it.
Diamond Polishing Paste. I Like this color coded stuff that is cheap and despite its lower price, seems to be well graded:
amzn.to/3oJEZLk
Mounted felt buffs. At least 10 of them, but It's good to have extras.
I am using these:
amzn.to/3x2aZyf
I run a Nova type wheel on my genie, which is a soft diamond cutting and polishing wheel. They can be ordered in sets of 6 here:
amzn.to/3qQKHhl
This stone is not yet for sale.
However, there are currently several Ethiopian opals listed on my etsy shop here which are over 10 carats and are priced at below wholesale costs:
www.etsy.com/s...
Disclosure:
I am a member of the Amazon Affiliates program and Earn a commission on any sales made through the links to the products I endorse. I make a great effort to only endorse products which I myself use and enjoy.

[@xXCybranXx]

As a raw stone it was a 10/10 for me. I like the hard edges and the natural looking.

[@MCC4RTHY1]

I would have left it as a specimen piece. It was so lovely

[@earthartgems]

If I could do it again, I certainly might do exactly that.

[@STLpsi]

Amanda Mc Carthy ... oh wow, rewound.. and ya! That was spectacular to start with

[@NATHAN-ILLUMINATI]

I do love the final product I must say....you also do have a valid point....but the fact that he put his heart and soul into the final product makes it more valuable and personal to me....it's LIKE having a Picasso in stone

[@josephcassady1816]

i though it was that much more spectacular as it was in the rough.

[@Royal_Fortune]

Honestly thought the same. It’s a shame because it looked so vibrant on its own.

[@samgulao]

Same here. Rough looks more radiant !

[@1.4142]

so much material was lost.

[@saudagar8974]

same here, rough is look awesome

[@cuthevayo5017]

Astounding in the rough👌...if there's a skill to just hive off grit & enhance the rough🤔🤔🤔

[@glennlaroche1524]

Opals are pure magic solidified.

[@zewdubelayethiopia9994]

wow my country Ethhiopia is blessed by beautifful opal!

[@okrox3887]

It was so beautiful before it was polished

[@geyotepilkington2892]

What a damn shame, that was such a beautiful stone to begin with. Better luck next time!

[@semperfidelis2970]

The finished product is breathtaking

[@skoitch]

Should’ve repaired cracks with opticon. It’s amazing stuff.

[@charlesteune6416]

Absolutely beautiful stone. Keep up the good work.

[@earthartgems]

thanks!

[@PeterParkerWebslinger3]

man, im sad to see that natural stone disappear...

[@hickamordue3228]

WOW! That was gorgeous rough!

[@arb7733]

Wow what a beautiful illusion from the shape of the stone and the sunshine does it justice 😃

[@Vidyaasshh]

That rough one is more spectacular

[@mariaherlihy2380]

*chuckle*. Just as I was thinking I would love to see that stone in the sun, you did it! Beautiful work.

[@niclasell2701]

SO beautiful! Looks like liquid rainbow on the inside.

[@ThuyNguyen-bu9ge]

How amazing and beautiful. The polishing craft work is exceptional too, good job!

[@jaywillzxrp2691]

Maybe this would look best with a diamond cut to better reflect the light in the stone and reproduce those beautiful colors before you cut it. Maybe those sharp angles pre cut is what was helping produce wonderful colors.

[@faithzebedee3405]

He wet sanded it. Ethiopian opals actually lose their colour when they get wet, and can take days to regain them.

[@serkanergun0]

I totally agree. the stone is too clear, it needs facets to reflect and create brighter shades. Otherwise it just turns into sone kind of lens :D

[@madimemixea8813]

i think this is one of the reason why all types of diamond and or gem are expensive cos they polish and cut it carefully.. to make it perfect

[@imzimansvideos]

If u treat it smoke or acid so it goes black will bring bak the colour but Ethiopian opal does do tricks and can look plain when water is introduced

[@twofeathersnmi]

For cracks you can put them in a hot pot with Hughes Opticon fracture sealer for 3 to 4 days, pull it out, clean with alcohol, then let it dry for 3 to 4 weeks. Works wonders! I use a Mini crock pot.

[@CC6_Fanclub_President]

You use Opticon on ethiopian? I always wondered about that

[@danvango]

I just started Opal Lapidary I buy alot of Welo Opals on Amazon, beware the treated stones, your tips are very helpful. thank you so much

[@earthartgems]

I had no idea you could buy opals on Amazon.

[@nackenbeisser]

Very interesting! It was so sad to see those cracks showing up... I am wishing you good luck that it won't crack much further! Very good policy not to sell stones that could still develop cracks. Good for your customers - and for you, of course, as it's always a great idea to avoid annoyed customers.

[@jessegill4925]

Looks like the arkinstone from the hobbit looks beautiful

[@shantishanti6343]

The rough one was the most beautiful you made a huge mistake

[@betterlatethannever4921]

The cracking was hard to see but you definitely made the best of it!

[@earthartgems]

It was hard to get it to show up on camera but it was obvious enough in erson that I'll need to cut it off and re-shape/polish. Hoping the third time is the charm!

[@joshharris3040]

How is it now several months later?

[@opalonly]

Would be nice to get more a out the stone. Thank you.

[@jerrymuns]

That is righteously gorgeous!!!

[@RenHonjou]

Nice video, liked 👍

[@earthartgems]

Thanks Ren!

[@ga1actic_muffin]

IT LOOKED BETTER WITH THE OPAQUE STONE ON IT!

[@easemailboxes]

Or you can treat it..... Oooops nobody does that do they. Great video. Top job.

[@user-es6cm3dz7f]

So gorgeous! I love your informative videos. This is Diann btw. I don't have my own KZbin account so I'm using my son's.

[@earthartgems]

Thanks Diann! Yeah, this was an interesting stone for sure. Make sure to watch the follow up video!

[@juliafayeconner8978]

That is really pretty.

[@miguelortiz5822]

Seems like he lost the beauty of it as he grinded it down

[@roughroosterknifesharpenin5531]

I agree

[@boredoflife8703]

Just like everything else human's touch, life could be beautiful in purest form but they started to modify it & it lost most of it's charm

[@animallanguage4271]

Wow lots of work and Knowledge!

[@jeremystark3350]

I liked it Raw untouched at the beginning, although both are nice.👏

[@earthartgems]

Honestly, Me too!

[@jumpchambers]

Nice work. That is absolutely stunning.

[@commonsense5489]

This is a beautiful stone my guy...

[@galaxyartstone]

This ‘non-hydrophane’ type opal material is probably better kept wet just as it comes out of the earth. It typically continues to craze over time no matter how much you remove and re-finish. They make awesome freshwater aquarium decor, and to keep them well preserved. Some may use oil treatments during the drying process to try and prevent crazing, but over time they eventually slowly craze the surface.

[@earthartgems]

So know you tell me!!! lol.... just kidding :) you're 100% right on this. But I have to say, the cracked up specimen makes for a great conversation piece.

[@PaulNurse1]

The real art would have been to leave it raw but what do I know. I just thought it looked beautiful as it was

[@IFIXCASTLES]

Crazy sparkles.

[@None888.]

I have some of this stuff...it's pretty cool looking but next to Australian opal it looks fake ..even tho I know it's not...

[@roughroosterknifesharpenin5531]

Why on Earth did you do that to such a beautiful stone?

[@yubz1496]

why would you not increases the value by a huge amount

[@roughroosterknifesharpenin5531]

@@yubz1496 if it's that rare, leave it alone

[@yubz1496]

@@roughroosterknifesharpenin5531 its how it works bud

[@marekkram4398]

Stunning

[@kevinprinceofdarkne]

Everybody seems to think it was better in the rough; either way, it is one truly beautiful stone.

[@earthartgems]

Yes, that does seem to be the general consensus Maybe I'll re-post this video... but it will be played in reverse!

[@martincrouch1821]

Beautiful beautiful stone

[@algert140]

Very beautiful stone

[@jesusyeshuaelelyonelshadai6295]

I thought you can seal the cracks heating it up on vacuum with resin.

[@STLpsi]

Interesting... and yes, “frame yourself in the name of the the Lord “Yod Hey Vav Hey”

[@cheekyj4794]

I was told that can't be done with Ethiopian opals (and only Ethiopian opals), all others can be "stabilised".

[@captainTubes]

@Dfg Sdfg unless it's Andamooka matrix opal. But that is always disclosed.

[@royalekhai8159]

i liked it better on the rough. it had more fire and character

[@MrDutchman100]

If you put it in a Ziploc bag let it dry slowly it won’t crack just a FYI. Take 24 hrs

[@sharoneastwood.1025]

Ain't it funny because I thought that it was much more beautiful before it was messed with.its like all the life and beauty was grinded away.

[@cathifamjourney469]

Very pretty!

[@iiihamzapoloiii]

Beautiful

[@1987stellalink]

Wow it’s stunning 😍😍😍😍😍

[@AdrianoPedrasPreciosas]

Ficou linda a gema

[@user-li6ho4hq7r]

so great

[@ramalama9030]

I have purchased a lot of Ethiopian opal and polishing it can be tricky because the color bars are very thin........if you remove too much all you have is a piece of glass.

[@josephswafford7578]

Unique. Specimen.

[@prashantagarwal6886]

Huge and beautiful stone, we also do manufacturing in Jaipur, India. 😊

[@lovelightopals6867]

Your going to have to cut and re cut it because it’s not stable material. What they call none hydrophane

[@thepowerandmiraclestory1565]

It's amazing and fantastic.

[@MB-wq8cp]

This guy made the opal look like a a cheap marble you could buy for 10c

[@marekkram4398]

If you cut it in half you have 2 good big places less chance of cracks

[@artandopal6600]

Looks great

[@cheekyj4794]

Have you tried to do a full dry cut and polish, I've cut many smaller welo opals this way and had no cracks. You just have to take it slow and as gentle as you can be.

[@weisswurstfruhstuck8523]

This is crystal non hydrophane opal. This will almost always crack even if you give it a bad look ;) for cutting gems you take the hydrophane opal. They don’t crack so easily at least. These stones are strange and amazing. They soak up water loose the color and need days to be dried out again and getting their full color range back :)

[@cheekyj4794]

@@weisswurstfruhstuck8523 ok, so how would a hydrophobic stone crack as the stone dries out. By its very definition it has no water in it, and how would that perform better than a stone that loves water (hydrophilic)? I literally have no idea how that would work, please if you know something I don't please share. I need all the knowledge I can get in my brain.

[@weisswurstfruhstuck8523]

Cheeky J no it’s called hydrophane. I was confused by this too first. I am cutting them myself now since a good while. I would explain it like this maybe. As the non hydrophane is so dry or not alive drinking and soaking water it cracks easily when watered or cut as gem. And the hydrophane they are living beings for me in the meanwhile now and they soak in the water dry out and therefore don’t crack. I first thought must be the other way round but it is not. World is a strange place and as these stones are very new last ten years I think discovered at all they are not fully understood too yet. And still new material is found there which all is different in how they react on cutting also. But overall you could say hydrophane is better chance to not crack. But even the hydrophane are very easy to crack when warmed up or even just soaking water again for the first time. This happens too. But as this non hydrophane crystal stuff anyway has not much color you rather go for the overall rule to stay cutting mostly with the hydrophane :) Hope I could help a bit. If you are more interested check the site of the GIA on welo opals. Ah and every stone has some amount of water in it always. But these hydrophane opals really seem to have their own lives and drink it up and dry it out :)

[@weisswurstfruhstuck8523]

Here is a article on opalauctions that might be of interest for you then too :) www.opalauctions.com/learn/a-z-of-opals/hydrophane-opal-information

[@cheekyj4794]

@@weisswurstfruhstuck8523 brill, thank for the info. A very good explanation, I shall keep it in mind when I'm next looking into Ethiopian opals. I'm currently trying to get some black opal from Indonesia, should be getting it in the next week or so. New play things are always good.

[@Soli_Deo_Gloria_.]

It looked way better as a specimen.

[@saiyidramdhani2379]

beautiful

[@STONES624]

Hello good morning beautiful champion your opal i will leave my like

[@asmaravilhasdocriadoretern133]

Olá amigo mais uma escrita 👌👌💎💎💎sucesso,👌

[@merryweatherflowers]

I think that’s nicer than Australian opel

[@randallbaker3809]

Very nice

[@BedfastSquid]

I would be so pisseddd if I was the one who sent you that opal.

[@TeguhSusanto]

Wow Good👍👍 boss

[@E3ECO]

I didn't know Ethiopian opal cracked so much.

[@weisswurstfruhstuck8523]

E3ECO this seems to be non hydrophan welo crystal opal from Ethiopia this is very likely that it cracks. Almost always. If you buy rough from welo be sure it’s hydrophane. Means that the stones soaks up water and looses all its color and if dried again gets back it’s colors. The non hydrophane is 90 percent to just crack and crumble.

[@SevenResources]

Non-hydrophane is for collection. it's found in spectacular sizes and breath taking color play but it has to be hydrated all the time to preserve it. I have 3.8kg, 1.65kg and many 1kg and half kg pieces but best kept as is in water. Looks like the cutter didn't know this was non-hydrophane. In the description section he wrongly said it was hydrophane, which is the stable type.

[@bunk9991]

If you took your time and kept heat to a minimum, could you work that stone without water? Its such a shame that Ethiopian Opal crazes so badly, it would be nice if someone could find a way to polish without water. Gorgeous stone BTW.

[@earthartgems]

Technically, yes, the main reasons for water are three-fold: 1. reduce heat/friction. 2. clean off the stone as it is cut. 3. reduce airborne particles. But this stone was doomed from the start I later found out. It was stored in water all its life and is a specimen grade opal, not cutting grade.

[@bunk9991]

Oh! I didnt know there was grades of Welo opal. Other than just good and lousy, I wasnt aware of "cutting grade". On many occasions I wanted to buy some off Ebay but was afraid of the cracking and crazing. I will look for the better grade in the future. Thank you for the info and response.

[@earthartgems]

@@bunk9991 I did not know this either until after this experience. I now know to ask a seller if it is "cutting" grade, or "specimen" grade. The later of the two are usually kept in water to keep them from cracking while cutting grade can be left out to dry.

[@bunk9991]

@@earthartgems Thank you for that info Austin. I used to cut aussie opal but its so expensive now, I cant afford it. I will use your knowledge to see if I can get a parcel of Ethiopian that is cuttable. Do you have someone you trust to buy opal from?

[@earthartgems]

@@bunk9991 You're very welcome. As for the rough, I cannot say that I do. I typically wait until the local gem shows and then buy my rough in person so I can inspect it and ask questions to the seller. But those only happen about 2 - 3 times a year and sometimes the vendors don't even show up... I kinda stopped cutting a while back unless a worthwhile piece comes across my desk.

[@semenhsisay5080]

Hello? do the hydrophenic or dry ethiopian opal also having a tendency to get crack after drayed on the rough stage?

[@PaddyMcMe]

See, I'm just getting into Opals, I love the Aussie Opal Hunter show, and I like the idea of being a gem shaper but jesus christ getting only 40ct out of a 250ct specimen is just too brutal for me. I get upset watching people shave a few ct off of other opals, this weird Ethiopian stuff is nuts. Is there no way to stabilise the stone? Or are you always at the mercy of it cracking later on?

[@earthartgems]

This piece was doomed to crack, regardless of if it was cut or not. Now that it is cut, I've kept it. It looks like crackle glass with blue and green color play inside. It's beautiful in its own way as the cracking occurred very uniformly; like the surface of a dried lake in the desert. I know there is a lot of debate about polishing vs specimen, but in the end, it's all up to the holder of the stone. And sometimes curiosity gets the best of you.

[@raphaelgabriel3912]

Quebrou a peça parceiro!

[@paranoidpony6861]

What's the point of letting it dry out and continuing to recut it? Just put it in a small bottle/jar of water or treat it!

[@Crumbcat4life]

You made a mistake with the opal when the sand was on the opal you made the opal wet and sand mixed with water causes cracks when ur polishing an opal you always need to get rid of the sand before cutting and polishing

[@Crumbcat4life]

This is the comment i was talking about

[@wqmanawqke3375]

Looks like a dragon egg. Shame it cracked but very beautiful non-the-less.

[@KlangTanz]

wow

[@moradadaspedras5074]

Q show, parabéns!

[@TravisChristopher]

That was a beautiful specimen. If you are going to cut it why not cut it for a setting?

[@zgjfinance2796]

I don’t know much but i feel like you dropped the ball

[@earthartgems]

It was a sacrifice I made to help others to learn. you say you don't know much, but now you know a little bit more.

[@Niccy07]

the whole beautiful stone gone... wtf???? 🤦‍♀️🤣🤣🤣☝️

[@sharoneastwood.1025]

He messed that up big time.

[@bobsjess]

I was wondering since Ethiopian opal is porous could you treat it like concrete opal or matrix opal from Australia with sugar and acid.

[@stonehand49]

The Tao of Ethiopian opal...

[@n.a.8050]

It's like a lava lamp!

[@vladimirofranzin8289]

Think is a so god stone

[@johngallagher9151]

I would have wire wrapped that thing as it was.

[@user-vd7yx6de4d]

Какие тонкие руки у вас ,неудобный станок

[@baguzgemstone]

Wow Bagus sekali batu nya

[@sela.kantu777gospel]

Uau!!! Linda Opala!!! 😲😲😲

[@kertbert1]

That jelly stuff was never stable. Maybe dried very slowly or maybe cutting dry. 80% of it cracked. Other welo was very stable.

[@zacklariviere816]

Now does the oils in his fingers have anything todo with the cracking?

[@mysterychannel6577]

Would it not be better to dry grind it if it can crack when wet?

[@NATHAN-ILLUMINATI]

THAT IS FUCKIN AWESOME.....I WANT ONE.

[@user-to3zg4yw7o]

Да чего красив опал

[@amaidolimasilva7321]

Amarildo Lima da Silva na frente dos estrangeiros só eles mesmo nota 10 pula pedra na mão e fica 10 ai que coisameu abraço felicidade para todos os garimpeiros que acredita no trabalho e a coisa da natureza coisa linda é nós tchau