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Frequently Asked Questions
What is Opal
What is an opal rub?
What cutting machines can I use to cut opal?
How can I start selling opal in my country?
What is opal made of?
Can I use a dremel to polish the opal and carve it?
What is nobby opal?
What is a Black Opal?
What is a Crystal Opal
What is Rough Opal
Where is Lightning Ridge
Can I buy and opal from outside Australia
What does Shipping Cost me?
will you cut opal for me?
How can I learn to cut opals?
Can you make jewelry for me?
What opal would be best for me
What is OpalWhat is Opal
Opal is a gemstone precious or semi precious that is naturally formed underground. The silica substance can form into amazing colors and patterns making opal one of the most unique gemstones in the world.
Silica the makeup of opal, which was formed from water and silica spheres, is what makes opal such a unique and colorful gemstone. The opal is formed underground where high concentrations of silica spheres are in the soil, clay and sandstone. When the water from rains seep through the ground the silica spheres are washed into cavities and crevasses in the ground to form over millions of years, what we call Opal. The cavities fill up with the spheres and harden. Depending on the size and structure of the silica spheres depends on whether the opal will have color play in it. If the spheres are evenly stacked together the opal will form color play and making the opal precious opal. If the silica spheres are stacked randomly with no even alignment the opal will have no color play and will be considered common opal.
Opal is found in many continents around the world and formed in different ways, but only few deposits actually make opal with color play. (Gem Opal)
The main countries that produce gem opal are, Australia, Brazil, Ethiopia, Mexico, USA, to name a few. The best of all the opal, deposits are from Australia where is the most rare opal is found. (Black Opal) This black opal is formed with a rare dark bodytone, which gives the opal color a brighter appeal to the color play. The black opal is quite an unknown opal by world standards but is very well known in Japan for the Japanese have found this black opal gem to be the best in world.
Opal is also formed in a crystal clear look as you hold it up to the light. There still can be colorplay but not as bright as black opal. The crystal opal is found in almost every opal-mining field and can reach some very high prices.
White opal is a more common opal and is not as valuable as the other types of opal. This was one of the first types found in the early days and now most people around know opal as white.
Opal can be set into jewelry and worn as the colors in the opal attract people’s attention. The amazing gemstone is more unique than any other gem as there is no single opal the same. There are many factors involved in opals uniqueness as the opal color play, pattern, brightness and body tone all are factors in opals diversity of types.
Opal has a hardness of about 6 to 7 on the hardness scale and is about the same as glass. Al little care is needed to keep an opal in top condition as the opal can scratch if rubbed against hard surfaces. When deciding on a setting for an opal, a good surround of the stone will help protect the opal from bumps and scratches happening.
The water content in opal is usually between 3% and 10%, but can be as high as 20%. Opal ranges from crystal clear through white, grey, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black. Of these colors, the red on black bodytone are the most rare, whereas white and greens is the most common. These color variations are a function of growth size into the red and infrared wavelengths. Common opal is truly amorphous, but precious opal does have a silica structural element. Opals are also Australia's national gemstone. Opal is one of the mineraloids that can form or replace fossils. The resulting fossils appealing to fossil collectors, although remain less significant for many scientists.
What is an opal rub?A rub is an opal piece that has been grinded on a wheel from the rough state on a opal cutting machine to show the approximate color, shape and weight of the opal. Another name is a preform opal.
What cutting machines can I use to cut opal?What type of opal cutting machines to use.
There are many cutting machines and ways to cut and polish opal. Finding the opal-cutting machine that suites you is the question that most people have on their mind when starting out.
When choosing an opal-cutting machine you have to take into account whether you are going to use diamond grits to cut and polish your opal or sandpaper, pumice powder, and cerium oxide.
If you decide to go all out using diamond grits to cut and polish your opal, you will basically only need three opal cutting machines.
Firstly you will need an opal cutting machine like a pixie or here in Australia we have machine called Gemmasta. These machines are wet machines and will hold all of the diamond wheels you will need to rough shape and polish your opal.
The most commonly used diamond grit wheels in my opinion are as follows
Wheel1: 240 grit hard diamond wheel for roughing out your opal to the approximate size and shape of you want.
Wheel 2: 600 grit hard diamond wheel for the finer shaping on the dop stick to get the shape and dome you want the opal to have.
Wheel 3: A 1000 grit soft nova wheel for smoothening the opal and giving the opal it’s round smoother edges and dome.
Wheel 4: A soft 10,000 or 15,000 grit Nova wheel to give you a final polish,
The thing about diamond wheels is that you will probably have trouble getting a really good polish. They have not perfected the polishing stages yet in diamond.
My advice is to purchase flat lap felt wheel and use cerium oxide with water to brush the cerium oxide using a clean paint brush to apply it onto the felt wheel, that way you will get the best polish possible. (Always re-applying to keep it wet)
The way I cut and polish opal is using hard diamond grits to start with, but then once I have finely cut the opal to the approximate size and shape, I then change to a flat lap 1000 grit wet and dry sand paper with cushioning as backing. (You must wear the sandpaper down with potch to get the right smoothness) This technique is an old fashion way but still I think the best and cheapest way to go.
Always using this part of the process dry. (A dust mask is handy to use)
Once I have sanded the stone I use a felt wheel with pumice powder and water to get the pre-polish, final shaping and adjusting done.
Make sure you wash the opal and your hands really wel so you don’t get impurities in the final polish otherwise you will get scratches in your opal
And then I polish with cerium oxide to finish the opal.
The back of the stone is smoothened out by re-gluing the opal upside down on the dop stick and smoothing the back to as fine a polish as you would like, sometimes giving you a double sided polished opal.
Lastly to become a great opal cutter I think it is important to own a slicer, to slab or split and take excess opal that is not needed away from the nobby.
A slicer also helps when the rough opal piece would be better cut into 2 stones.
Or there is more than one colorbar in the piece.
I hope this has been useful to you.
How can I start selling opal in my country?Starting an opal business is just like starting any other business. It's mostly about people, If people like you and what you stand for, they will buy from you.
You can start selling at local markets and jewellery stores, or once you have trust you can start leaving you opal on consignment with jewlellery stores.
Once you established your market. It's all up from here. What is opal made of?Opal is made of silica spheres that are collected together in conglomerates and fissures in the ground. WHen the rain falls the water carries the silica shperes throught the ground until it fills a cavity in the ground and turns into opal.
When the spheres are stack very neatly (done by mother nature) thus creates color.
When the spheres are large and small and stacked unevenly, you get opal with no color called potch. Can I use a dremel to polish the opal and carve it?Dremels are used mostly for carving opal and taking sand spots out of opal.
They are a very handy tool to have if you are working with opal. What is nobby opal?Nobby opal is a form of opal that comes from Lightning Ridge only. It takes the form of a rounded cavity underground instead of a fault line that seam opal is formed in. This nobby opal has produces some of the best quality black opal in the world. What is a Black Opal?A black opal is an opal mainly only found from Australia in Lightning Ridge. The black opal is a dark bodied opal with a natural black backing to give the opal a rare dark mystique vibrance. The color usually shows up much brighter than a white opal. What is a Crystal OpalA crystal opal is an opal that has a translucence to it. When held up to the light, you can see through it like a piece of glass. But when you hold away from the light the colors show up on a beautiful colorplay. What is Rough OpalRough opal is the raw material that has come out of an opal mine. It is uncut and unrubbed. Where is Lightning RidgeLightning Ridge is situated 70 kilometers south of the Queensland Border in New South Wales, Australia.
It is 750 kilometers from Sydney and 800 kilometers from Brisbane. Can I buy and opal from outside AustraliaYou can buy an opal from me and I can ship it to you just like most of my customers.
You just choose your country in the checkout and the shipping type you like. What does Shipping Cost me?There are 3 choices for shipping on this site.
1 Registered Interational mail takes up to 2 weeks.. costs $12
2 Express Mail Service takes 3 to 7 days $45
3 Inside Australia it is a local Express Post Platinum of $12
Special shipping can be arranged with Fed Ex. Just ask. will you cut opal for me?I can cut and polish opal for you at only a few pieces at a time. Costs are $20 per stone. How can I learn to cut opals?You can look to my opal videos on the top of the website and see many videos to learn to cut and polish opal. Can you make jewelry for me?No I dont make jewelry as yet. Sorry What opal would be best for meAll opals are different colors, sizes, shapes and patterns. To choose an opal to suite you I wouls choose the colors that you like best and go from there. Also you can make your descidions by the environment you live in. For example.. If you live near the sea blue and green colors would suite you. ANd the same for arid or red dusty farmlands. You can choose red, orange or blues as the sky is everywhere.
Mostly opal will choose you and you dont get much choice in the opal you want. When you see it you will know.
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