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Gemstone Identification Natural verses Man-Made


#1

Hello everyone I am new to Gemstone identification

I have acquired several stones just to test and get comfortable with the testing
One of the Stones is a Blue/Clear 20 carat Stone

Color
Density and RI show it to be in the Quartz Family
I have investigated color and clarity and I am stumped - how do you tell the difference between Aquamarine and Man-Made Blue Quartz???


#2

I feel pretty confident saying just by a cursory glance (which is VERY rare) that it isn’t aquamarine. My guess is “man-made” material…

Likely glass, is my guess. https://www.gemsociety.org/article/glass/


#3

Hi just on this subject, if the RI and specific gravity indicates quartz, then if could not be Aquamarine as the RI and SG are totally different to quartz.
I also agree with the editor, the colour is totally wrong for Aquamarine even if you didn’t do an RI and SG
thanks


#4

Thank you - I am reexamining the stone - I obviously have something wrong


#5

Thank you I am reexamining the Stone - I obviously have something wrong


#6

As You can tell By my freshly uploaded self portrait I have issues with my eyes - LOL
Thank you for your honest replies it forced me to repeat my testing

First thing I did was order a Computerized Refractive Index Meter to take my Eyesight out of the equation - Wish I could afford a computerized Spectroscope

Here is what I found and my conclusions
Shape - Oval
Weight - 19.95 Carats
Color - Blue Changing to clear
Hardness - 7-7.5
Specific Gravity/Density 2.59
RI - 1.546
Color Of Streak - White

Conclusion - Iolite


#7

So how did you rule out assembled stones?


#8

OK - I also bought a 20x to 200x USB microscope that is viewable on my Computer and it shows no layering or separate colors

Stone is pretty clean except some surface marks on the lower facets


#9

Hi :slight_smile:
I think/“feel” syntetic .,

BUT …if it is Iolite …IF ??

In that size and “close to picture image” , BIG CONGRATS :slight_smile:

(IF, IF, IF :wink: )


#10

Hi, I have noted on a fair few of the forum discussions that when people are referring to an RI of a gemstone they only state one (1) Refractive Index for a gem that is doubly refractive “Anistropic”

just wanted to say if you do not undertake a proper RI Test then you cannot add this to the list of tests you need to undertake to identify a gemstone natural or synthetic
one RI reading indicates single refractive index “isotropic” glass spinel garnet diamond etc
if you are going to do an RI test on what you believe is an “anistropic” gemstone doubly refractive then you must take the lowest and highest reading by rotating the stone 360% on the refractometer to get the actual birefringence of the stone
then you have the real RI.
Unless of course your reading is down the C axis which will show a single RI on a doubly refractive gem. which of course you need to check on another facet besides the table

thanks