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@Akumar,
Not all natural blue sapphire will show you inclusions. A lapidary cuts a stone in such a way that inclusions are hidden near girdle and culet making top facets part clean and clear.
If your gemmological lab says it is a natural gemstone then it can be but it is very diffcult for even gemmological lab to verify the origin of gemstone.
For maximum benefit and astrological point of view it is advised that gemstone ring should be worn on specified finger.
Sapphire and Lapis Lazuli are completely different stones.
- Sapphire comes in transparent to opaque while Lapis Lazuli mostly comes in opaque.
- Sapphire chemical composition is different than Lapis Lazuli.
- Sapphire comes in many colors like: green, pinkish orange, pink, white, yellow, etc. but Lapis Lazuli comes in blue, greenish blue or purple blue color.
- Lapis Lazuli is a mixture of several minerals that’s why it’s a rock; while Sapphire is not a rock.
- Both of them appears different visually.
- You can find more details at http://www.gemstonebuzz.com/lapis-lazuli and http://www.gemstonebuzz.com/sapphire
Hope this helps you.
Assuming 5 carat stone with top clarity, cut and color the gemstones will rank in the following sequence for their expensiveness:
1. Ruby
2. Diamond
3. Emerald
4. Sapphire
5. Pearl
6. Garnet
7. Aquamarine
8. Chrysoprase
9. Topaz
10. Citrine / AmethystBeryl should not be on the list as beryl is a group which includes both Emerald and Aquamarine which has already been listed above.
The reason why Ruby is ahead of Diamond is because the most expensive stone in the world which has been sold till date is Ruby, namely Burmese Ruby which are now days very rare as those mines from which they were mined has been legally sealed.
Some other stones which should be in the list are:
1. Alexandrite
2. Lapis Lazuli
3. TanzaniteThe possibilities can be:
- Lapis Lazuli – The appearance. Low quality of lapis lazuli without pyrite crystals/lines.
- Dyed Quartz – Since the stone has a high concentration of colors at some areas, it shows an indication of dying.
- Sodalite – The appearance.
- Dumortierite – At first glimpse, I thought it is Dumortierite as I have seen some similar stones in past.
The stone cannot be concluded as “Sodalite” unless R.I. & S.G. are taken.
Great to have you Candy.
This is a small community but slowly growing, but people around here are very helpful.
Generally, heat treatments are done in “natural gemstone” but heat treated “synthetic gemstone” are also available in market. Since your blue sapphire is said to be heat treated so it should not be synthetic but this should not be taken as confirmatory. Only a gemological lab or expert in gemological field can ascertain whether your stone is natural or synthetic after instrument testings.
“Rule of Thumb” – If a gemstone is very clean and price is very low then chances are that the stone is synthetic / fake.
The gemstone shown in the above link should be blue sapphire.
Since this gemstone is very clean it is not possible to make out whether it is natural or synthetic under the basis of picture.
Sapphires (mostly yellow and blue) which comes from Bangkok (Thailand) are mostly heat treated. Even “natural colorless sapphire” are converted to “natural blue sapphire” with heat treatment.
People dealing in hessonite garnet can identify this stone just under the basis of its appearance (heat-wave effect) and color (orange-red, brownish red, orange-yellow). But 100% confirmatory test can only be made with the help of gemological instruments (refractometer and spectroscope).
Hessonite garnet can be identified with heat-wave effect which appears as hazy appearance or distorted appearance inside the stone. For a common buyer it is not possible to identify hessonite garnet just by visual appearance because they won’t be able to make out how heat-wave effect looks.
There are other gemstones (yellow sapphire, yellow topaz, natural yellow zircon) in trade which appears similar to hessonite garnet so it is difficult for a common buyer to identify if a gemstone is hessonite garnet.
To find more details on which finger a ring should be worn for other gemstones, click here
In market both natural and synthetic blue sapphires are available. Separation of natural blue sapphire from synthetic by naked eye is nearly impossible, even gemologist fail at certain level to separate them visually. The natural sapphires that we get in market are mostly treated (heat & diffusion). It is again difficult to identify these treatments with naked eyes.
First, never ever separate a blue sapphire from other blue gemstones only on the basis of shade, since blue sapphire comes in all shades of blue.
There are basically 5 gemstones that appear (replicate) as blue sapphire. These are Synthetic Cubic Zirconia (a.k.a. C.Z, American Diamond), Iolite, Tanzanite, Benitoite and Man-made blue glass.
Separation of Blue Sapphire from:
- Blue Synthetic Cubic Zirconia (C.Z.): Blue C.Z. is the most common substitute for Blue Sapphire. An experienced gemmologist or trader can easily separate Blue C.Z. from Blue Sapphire even by weighing these stones on hand; because if we take same volume of Blue Sapphire and Blue C.Z. then Blue C.Z. will be heavier as its specific gravity is more. Also, C.Z are often eye clean but sometimes have zirconium oxide “powder droplets” which can appear as rows of dots.
- Iolite: If Iolite is rotated from different direction it will show a shade of yellow which doesn’t appear in blue sapphire. So if your blue sapphire doesn’t show yellow shade then you can be certain that it is at least not Iolite. Note: Sometimes iron staining in blue sapphire can be the cause for yellow shade. So this is not conclusive evidence.
- Benitoite: Benitoite is a rare gemstone and it is less likely that you will encounter it. However, you can separate Benitoite with “doubling test”. When you look through facets of Benitoite towards culet, culet will appear as two. Even inclusions inside Benitoite will sometimes appear as two. This is a confirmatory test as there is only one natural blue stone with doubling effect.
- Tanzanite: Tanzanite shows three shades of blue when looked through dichroscope whereas blue sapphire will show only two shades of blue. You can also separate it with instrument called refractometer. Eye separation of tanzanite from blue sapphire is difficult. It requires certain instruments to get it separated.
- Man-made Blue Glass: Glass is a good simulant for all gemstones. All man-made glass has “gas bubble” inclusions which appears as round or oval or elongated. New people might find it difficult to identify & separate “gas bubbles” from “crystal fingerprints” but with few practice one can easily separate between “gas bubbles” and “crystal fingerprints”.
Blue sapphire (variety of corundum) is generally heavier than all these stones (Iolite, Tanzanite, Benitoite & Man-made Blue glass) except Synthetic Cubic Zirconia (C.Z.). That is, if the same volume of these gemstones are weighted blue sapphire will weight heavier.
Refractometer is an instrument which checks the R.I. (refractive index) of gemstones. It is a “life saver” for many people involved in gemstone trade. One can separate more than 50% of the gemstone solely on the basis of this small instrument. I personally suggest everyone involved in this field to buy this instrument.
A word of caution: If you are even 1% unsure whether your gemstone is genuine or not then it is highly recommended that you get it certified from a reputable/trusted gemological lab.
Updated On: December 14, 2012: Added Synthetic Cubic Zirconia as a substitute for Blue Sapphire and made minor correction to the post.