I was a bit bored and came up with a new and easy quiz, winners name get written in the "eternal fame" booklet (best answers of course).
1. what is a "kerf"?
2. given 2 flawless colourless brilliant cut stones, synthetic moissanite and zircon; which tool or technique would you use to seperate the two.
3. which uses has silicon carbide in the jewellery industry?
4. the "critical angle" of a gemstone depends on which values?
5. how many minerals end with "ite" and name them all.
1.The width of a saw cut is called kerf. That's an Anglo-Saxon word related to our word carve.This results in wastage as the saw cuts a stone the width of the saw or 'kerf' is destroyed.
2.I would use a specific gravity test, weighing each stone in water and air,zircon is very heavy so should stand out quite easily.
3.Silicon carbide is used through a sublimation technique,to create colourlless gem quality synthetic moissanite.Also used by bench jewellers and lapidarists as 'Carborundum' to sharpen instruments.Silicon carbide is used to grind,saw,drill and polish gemstones.
4. the critical angle of a gem,is dependent on the 'refractive index' of the gemstone.This is determined through Snells law.The sine of angle of incident light/sine of angle of refraction.The optical density of a gemstone will slow down and bend the incident light.
The critical angle can be determined by the formula: sin-1(1 / n). where n is refractive index.
5.there are 2461 minerals ending in 'ite'
and here they are
1. I was thinking more in relationship to gemmology (and I don't think the etymology is English, contrary to what m-w.com says)
2. Yes that would work, there are some more quicker ways though.
3. Very good, there is also another use.
4. uhm, close but not good enough.
5. LOL too funny (you missed atleast one)
ok
1.a kerf is used in cleaving diamonds?A second diamond is used to make a notch called a 'kerf' by rubbing it against the other diamond’s edge. A steel blade is then placed in the kerf . A tap on the blade and the diamond will split.
2.you could try to get the two stones to scratch each other,whichever stone is scratched is your zircon.
3.silicon carbide can also be used in induction furnaces as an electrode that can prolong furnace life?This avoids problems associated with thermal shock and temperature gradients in traditional resistance type furnaces and electrical arcs.with uses such as heating stones and smelting your gold.Also used in blue led lights for making your jewellery displays more sparkly!!Silicon carbide fibres can add strength to alloys.
4.the critical angle of a gemstone depends on its refractive index and the RI of the other medium,which is usually air unless scuba gems are popular!!
5.I have not missed one!!!or have I?prove it
1. Indeed.
2. Remind me not to send any stones to you for analyses (but good), some lesser destructive techniques are available.
3. Yes, there is another use aswell (usually used by appraisers and jewellers).
4. That is the correct answer.
5. Typing out the list as we speak, will get back to you in the new year on that.
i saw this and immediately startes to look up the answers, im just learning s i had to research my answers so he goes I AGREE WITH STICKY JUST KIDDING . I sort of found the same answers but here goes. # 1 A kerf is a shallow saw cut usually less than an inch deep. Its done to give greater control on how to reduce a big stone into smaller stones. # 2 R.I , S.G , hardness test I use a refractometer to find the R.I , water n air test (snells law), mohs hardness test . # 3 Moissanite is a silicon carbide, and can be used as an abrasive and on cutting tools , plus inside the crucible ,like Sticky wrote. #4 The critical angle depends on the R.I. of the stone # 5 i think sticky covered them all.
right
1. done
2.The 'dot test' will seperate zircon from moissanite,the zircon will show multiple dots on pavilion facets,moissanite will not show this.
3.the other use for silicon carbide is in photodiodes,UV LED's, and photodetectors of UV light, with many uses in the spectral analysis of gemstones.
4.done
5.correct (bet you can't find one i missed)!!
We've got some great answers here, but if I had to separate moissanite from diamond I'd use a loupe, and if I still wasn't sure I'd just use the Presidium DuoTester!
Joined: Sun Oct 16, 2005 12:22 pm Posts: 21602 Location: San Francisco
If you place moissanite on a hotplate, and turn it on, the moissanite will change to an intense yellow....it will return to its original color upon cooling.
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