How to care for opals and opal jewellery
By Paul Sedawie
President of the Opal Association Inc
One of the most common misconceptions is that oil or house hold liquids can damage Australian opals. At present there are no known compounds that can penetrate a solid Australian opal. The only exception to this is matrix which is very porous. Another myth is that you should soak your opal in water; it does not need this to be done. Nor will enhance it, as a solid opal is impervious to this. It will not harm the stone so if you feel like doing it go ahead. Opal is a dress stone with the same hardness as pearl. Thin stones should be set in a pendant and not a ring. I have had a opal bezel set in a ring for 20 years and wear it all the time but every two or three years I have to re-polish which I can do leaving it in the ring. When set in jewellery the stone should be protected and not protrude out. Opals don't like to be stored away for years in a safe or exposed to strong sunlight. To clean your opal just use a soft brush or cloth and mild detergent - don't clean it in a ultra sound as you can damage the stone.
To view your opal at its best indoors, the natural light should come over your shoulder. Have your back to a window or door and view your opal.
These are both having natural opals, which are glued together, so it is not recommended to soak in water. Triplets can lift after time but now cutters use a UV light which seals it better so ask the seller if the triplet has been UV treated. Clean with a soft cloth with mild detergent.
This is what the GIA in American said about this opal
"The hydrostatic SG of the opals ranged from 1.80 to 2.10. This broad range is in part due to the high porosity of some samples, as revealed by a significant weight increase after immersion in water (up to 8%). Fluorescence varied from inert to moderate yellowish white to both long- and short-wave ultraviolet (UV) radiation. Samples that were inert displayed an unexpected greenish phosphorescence of moderate intensity. No luminescence was observed in the opals with a yellow-to-brown body colour, even the light ones; these darker body colours are probably due to the presence of iron, which quenches luminescence. The yellow-to-green luminescence is likely due to the presence of uranium."
This is opal from the Welo region of Ethiopia - it is mainly Hydrophane in that it absorbs water and can change colour. To determine if the opal is hydrophane wet you hand and place it on top of the rough - if it sticks to your hand it is hydrophane. Stones will change colour when wet but will return back later. Do not dry out under strong lights.
Also called brown opal
This material is more prone to crazing but they make stunning specimens with electric neon colours. This material can be stabilized and there are instructions in the forum on this site.
Virgin Valley Opal USA
This crystal opal has high water content and is prone to crazing. Some wood replacement opal makes great specimens and appear stable. Many of the miners do treat their crystal stones - there are instructions in the opal cutting section in the forum under Ethiopian opal as the treatment is the same.
The same care as Australian opal is needed. Some natural stones have matrix around the which can absorb fluids and discolour the matrix so clean the stone with a mild detergent.
How to care for opal jewellery
There seems to be much confusion about the proper way to care for and clean opals and opal jewellery. Here's a simple guide that will let you preserve your beautiful opals and keep them looking their best.1. Buy quality stones from a knowledgeable dealer or jeweller, preferably someone who is a cutter.
- Now this may sound like strange "care" advice, but the stone you purchase is as important as the care you give it. Here's why.
- Many jewellers don't know one opal from another, and cannot offer you the right opal care advice. If you know what you've got...you can know how to look after it.
- Yes, there is no problem in doing this, but if the stone were an opal doublet or triplet, it would be unwise to leave it in water (particularly hot water with detergent. as in washing up water) for long/extended periods of time. The opal triplet I gave my sister-in-law was used in all sorts of situations and was still going strong after 2 years of constant use...but this is not recommended for triplets and doublets as it may affect the cement that holds the protective crystal cap on the stone. Of course in the case of solid opals, hot water or detergent or oils will not affect them.
3. How do oily substances affect an opal?
- If you mean wearing it under the car when you change the oil or pack the wheel bearings,the oil won't soak into the stone or hurt it in any way, but the grime and the possibility of scratching it would be the biggest problem.
- However, oily hand and face creams will not hurt the stone, except that it may build up around a ring and make it look unsightly.
- Don't wear it doing the gardening, because the sand or soil may take the polish off the stone, or, if you get too energetic, you could smash the stone against a rock, and opals don't like being treated that way. (Neither would you or I). And of course, there is the chance that the gold or silver claws will be damaged, and you could lose the stone altogether. Take it off if you are doing any sort of work that could bring the stone in contact with hard surfaces. A flick of the wrist in the wrong direction could chip it.
5. What do I do if my stone loses its polish or becomes scratched?
- Now, this is why we suggest that you buy from people who cut the stone. For example if you get a stone from the Opalmine.com site, or from St Claire Opals, and you damage your stone, in most cases it can be re-polished very cheaply.
- Generally it's safe to store them away, as long as the area is not overheated. It's not a bad idea to put them in a sealed plastic bag with a damp cloth in case of drying out. Don't store them for long periods of time under hot lights, as this could crack the stones if the heat builds up and is magnified in a showcase.
- If you have accompanying diamonds with your opal jewellery, in the case of rings particularly, the diamonds become very dull after a while, even if you've given the ring a clean. The main reason for this is that many people only clean the front of the ring and not the back. So...just poor some pure washing detergent into the back of your ring, and scrub it from the inside with a soft toothbrush in hot water. The diamonds will sparkle again, and it will not hurt the opal as long as you don't do it all the time.
8. Check your jewellery.
- Inspect your jewellery regularly for claw damage. You can do this yourself if you have a magnifying glass. There's no mystery to it. If you can see that the claw is loose and the stone moves a little, it's good to get something done about it. If you hold the item up close to your ear and rattle it, if the stone is very loose you can hear it. If you want to be sure about it, talk to your jeweller.
- Any paste or fluid designed to polish brass will also polish gold or silver. Just use a soft rag, apply the paste, and polish it off. After that, pour on a few drops of household detergent, give it a scrub with a fine toothbrush and wash it off under hot water. This will bring the gold back to what it was like when you purchased the jewellery.
- Toothpaste and a soft toothbrush do an excellent job on both stones and metal.