The grade of this parcel is in the Auction Title. The description of that grade is down below.

Learn how to work this material:

One minute version here:

https://www.opalauctions.com/products/andamooka-matrix-treating-lesson-53frogs-1333244

Longer more detailedversion here:

https://www.opalauctions.com/auctions/how-to-cut-treat-and-polish-andamooka-matrix-opal-53frogs-795583

There are a few different types of matrix opal found in Andamooka, and this Rainbow matrix is the most porous of them all. It is sometimes called "Concrete" due to the conglomerate embedded within the quartzite matrix and the general resemblance to building concrete in its untreated state. The treatment process darkens the quartzite base so the Opal can be seen more clearly, and the Resin, if you choose to use it, creates an even surface that can be brought to a high polish.

DESCRIPTION:

Item Type: SOLID NATURAL ANDAMOOKA MATRIX Rough OPAL

Origin: ANDAMOOKA Australia

Number of pieces: 1

Treated/Untreated: TREATED-CARBONISED

The grade of this parcel is in the Auction Title. The description of that grade is down below.

Welcome to 53Frogs, where we run hundreds of no reserve auctions every week! But with all of those auctions spread out across so many different categories on Opal Auctions, it can be a bit overwhelming to find them all. The best way is to go to our shop 53frogs, then sort by "Auctions" and then by "Time Left"

or you can copy and paste this link

https://www.opalauctions.com/stores/53frogs?query=%22NO%20RESERVE%22

And don't forget - if you're buying multiple items from our shop, we offer automatic combined shipping to help save you some extra cash. Just make sure to pay for all of your items at the same time to take advantage of this offer.

Now, a quick word about our return policy: if you're not completely satisfied with your opal when it arrives, you're welcome to return it for a full refund. Just keep in mind that once you alter or cut the rough opal in any way, it becomes yours and we cannot offer an exchange. So be sure to think carefully before you start cutting! And if you do decide to alter your opal, please remember that by doing so you are accepting ownership and cannot leave negative or neutral feedback.

Oh, and one more thing: the images of our rough opals on our website are taken with water to help show off their beautiful colors and patterns. So be sure to keep that in mind as you're shopping.

We grade our opal in ten different categories as per the table below. The grade of this parcel is in the Auction Title.

Grade Description

#1 Top Grade-Mostly Reds/Pinks- Dark/ Patterns -Expert Cutters

#2 Very Bright- Clean- Mostly Red/Orange/Yellow -Expert Cutters

#3 Gamble- Red/Orange/Yellow -Nice Blue/Green --Expert Cutters

#4 Very Thin or Carving material- Intermediate/Expert cutters

#5 Large Single Gamble piece - from Beginner to Expert cutters

#6 Mid Grade Easy cutters - Intermediate cutters

#7 Mid Grade Gamble Rough- Intermediate cutters

#8 Beginners Cutting Rough- Beginning cutters

#9 Craft Material- Not Appropriate for cutting cabs

#10 No Colour Potch- Not Appropriate for cutting cabs

Thanks for stopping by 53Frogs. My name is Riley, and I'm a seasoned opal cutter with a lot of experience working with this beautiful and sometimes tricky material. As a young cutter, I remember how hard it was to find smaller parcels of rough opal that I could afford and that weren't just a bunch of potch (a type of opal with little to no play of color). That's why I've broken up a bunch of substantial commercial parcels of opal rough into smaller lots and made them available here for you.

We put a lot of time and effort into grading our opal rough to make it easier for you to find the perfect piece for your skill level and budget. And please, don't buy cheap, beginner-level rough from us and then give us negative feedback because you weren't able to cut a zillion-dollar gem. It doesn't work that way - cutting opals is a journey, and there will be ups and downs along the way. I've cut tens of thousands of opals in my time, and although I won't get it right every single time, I think my grading system is pretty accurate. My goal is to help make your cutting experience enjoyable and rewarding, and to help you avoid some of the costly mistakes that beginners often make.

So, what exactly goes into our grading system? Here's a quick rundown:

#9 "Craft Material" is not suitable for cutting cabochons. It's best for chipping and using in floating pendants or other craft projects. If you're looking for cheap material to set in your front yard or spruce up your bathroom mosaic, this might be for you.

#8 "Beginners Cutting Rough" is perfect for getting a feel for cutting opal without worrying about destroying valuable stones. It's a mix of nobbies (a type of opal with a nodule-like appearance) and seam opal (opal that is found in thin layers within rock), and it will yield lots of picture stones (opals with patterns or images) and low-value opals. This is a great way to learn how to cut open nobbies, chase color bars (bands of color in opal), deal with sand (a natural occurrence in opal), and get a general sense of what it feels like to cut opals.

#7 "Mid Grade Gamble Rough" is perfect for honing your skills and learning to read trickier opals. This material is full of thin color bars, diagonal color bars, wavy color bars, tricky sand spots, and blind stones (stones that have color in them but it's unclear how deep it goes). This material can be very challenging, but also very rewarding.

#6 "Intermediate Easy Cutters" - as the name suggests, this material is suitable for intermediate-level cutters. You should be able to cut medium brightness, sellable opals from this material. They are generally clean, and you should have a good idea about the kind and size of finished opals you'll be able to cut by watching the videos.

#5 "Large Single Gamble Pieces" - these are exactly what they sound like: large pieces of opal rough that can range from beginner to expert level in terms of difficulty. Cutting big stones like this is a very different skill from cutting small "pointers" (small, pointed pieces of opal rough) or standard 1ct-3ct opals. These are great fun to cut and can be very rewarding if you get lucky.

#4 "Very Thin/Carving" - most of this material is super thin and suitable for making doublets (opals with a thin layer of opal

#3 "Gamble Expert Cutters" these look very bright/colourful and show good promise, but I can't see that they will cut a clean opal. The best blue/green material I find in the parcel also goes into this bucket.

#2 "Expert Cutters Clean" will generally give you precious bright sellable stones. They appear very clear to the eye. It looks like the colour bar covers most of the stone.

#1 "Top Grade" this material represents only a small fraction of our inventory. It is the very best material we find. Red on Black, Deep pinks, lovely patterns, strong black opals all ends up in this category. If I yell, "WOW, I want to cut this one!" it goes in this tiny dish.

Before you make your purchase, there are a few things you should know:

Please check out within 7 days of your first win. We can not hold your pack after you check out. Once you check out your pack will be lodged with Australia Post in the next Monday/Thursday shipping window.

We ship all items within 48 hours of payment, unless it's a holiday, in which case we'll ship on the next working day.

Standard shipping typically takes 5-21 working days to arrive. Please note that the buyer is responsible for any customs/import duties or taxes levied in their country.

Our guarantee: We want you to be completely satisfied with your purchase from 53Frogs. If for any reason you're not happy, you can select a no-hassle return as long as the material is in its original condition. Just send it back (unaltered) within seven days of receiving it, and we'll process a full refund for your purchase minus the shipping cost as soon as we confirm that the items are in their original condition.

Thanks for choosing 53Frogs, and don't hesitate to reach out if you have any questions or concerns. Happy shopping!