Rough Amber Inclusion

[sharktooth1996]

Hello all. I went to a show recently and purchased this piece of amber with an apparent spider inclusion for $78. I don't have all the materials to do testing, but the piece has no taste. Could anyone help me determine if this is legit by looking? 

[Tidgy's Dad]

Can't tell from this photo.

But here are some tips :

1. Does it feel warm to the touch?

2. If you don't mind leaving a small mark use a very hot needle on it. If it's fake, the needle will go in easily and the smell will be plastic or pine (if it is copal). If amber the needle will encounter more resistance and the smell will be different. (can't describe it, sort of like an old tree). 

3. Scratch it with a needle. Glass will not scratch, amber will. (and plastic).

4. Get a mug and fill with water. Add half a dozen teaspoons of salt and stir well. Put in the amber. If it floats, it's amber. 

5. Static test. Amber will become electrostatically charged if you rub it on a woollen jumper. You should then be able to use the amber to move strands of hair or pick up tiny pieces of paper.

Obviously, be careful! Some of these may slightly damage your specimen. 

[Tidgy's Dad]

Oh, and a very warm welcome to TFF from Morocco! 

[snolly50]

Put a small drop of acetone (finger nail polish remover, check the label) on a flat area. Allow it to evaporate. Touch a tissue to the spot. Is it sticky? If so, it is not amber (amber is impervious); younger resins will partially dissolve (sticky). The other methods Tidgey's Dad put forth will help spot synthetics. The acetone trial is the best, I think, to distinguish ancient amber from copal. You will note that several of the test options will alter the piece (needle, acetone), but the acetone is only mildly destructive, if the piece is not amber. If it were mine I would perform the non-altering tests and, if it passed, try the acetone.

 

Just from the photo your piece looks "real." Good luck, have fun.

[caldigger]

Just to through my opinion in the mix.  The way your spider is in there tells me it's likely not a fake. They will usually try to position the "inclusion" in a perfect position to make it more aesthetically appealing. 

Having your little guy off to one side and curled up does not raise red flags with me.

Spiders in amber are common enough not to fake. When they do create forgeries, it is normally something big like a tarantula or other large insect.

[sharktooth1996]

I ran some tests--left it in a refrigerator to see if it would stay warm (it didn't, but warmed up extremely fast), static test (negative), etc. So I brought it to a jeweler I know and he ran it under microscopes of different varieties and under one kind he did some sort of measurement test. It measured out to be something like 1.54 or 1.5.4 or something like that, which the device said equals amber, and which he explained to me. Is this method legit? 

[ynot]

22 minutes ago, sharktooth1996 said:

I ran some tests--left it in a refrigerator to see if it would stay warm (it didn't, but warmed up extremely fast), static test (negative), etc. So I brought it to a jeweler I know and he ran it under microscopes of different varieties and under one kind he did some sort of measurement test. It measured out to be something like 1.54 or 1.5.4 or something like that, which the device said equals amber, and which he explained to me. Is this method legit? 

Your jeweler was probably looking at the refractive index.

Every clear material has a distinct refractive index and it is one of the most reliable tests for mineral IDs.

[snolly50]

@sharktooth1996

 

Did the jeweler place your specimen in a weird scale thingie, where the piece was immersed in water? It sounds as if he measured Specific Gravity (SG). SG is the relative density of a stone compared to the density of water. The formula being, SG = wt. in air/wt. in air - wt. in water. It is used as a positive ID for gemstones. However, the SG for amber is 1.5 - 1.10. For copal (a likely faker) the SG is 1.03 - 1.08. So, your measure of 1.54 is not diagnostic. It's close - but wait! Your piece has a large inclusion (departed spider); the 'rantula's SG is being figured into the mix as well! So the range for "pure" amber is not applicable. 

 

My believe is that the most likely scenario for you piece not being genuine amber is that it is copal. The way to tell the distinguish copal from amber is the acetone trial outlined above. Copal is actually viewed as "young amber." It is just not old enough for the molecules to completely polymerize. As I said above, I am inclined to believe your piece is amber. Test it with the acetone. If it has no effect - AMBER, if it gets sticky, copal. 

 

As an aside, amber should take on a static charge, however; I suspect that high humidity is impacting that test. 

[ynot]

26 minutes ago, ynot said:

55 minutes ago, sharktooth1996 said:

 he ran it under microscopes of different varieties and under one kind he did some sort of measurement test. 

 

 

 

11 minutes ago, snolly50 said:

It sounds as if he measured Specific Gravity

Never heard of specific gravity being done with a microscope.

[snolly50]

26 minutes ago, ynot said:

55 minutes ago, ynot said:

1 hour ago, sharktooth1996 said:

 he ran it under microscopes of different varieties and under one kind he did some sort of measurement test. 

 

 

 

39 minutes ago, snolly50 said:

It sounds as if he measured Specific Gravity

Never heard of specific gravity being done with a microscope.

Had I seen your initial post, added as I fooled around in generating my response; I would have been much less certain in my view.

 

Thank you.

 

Indeed, I am incorrect in my assumption, as to what was done. Upon rereading the original description of the tests made, microscopes are the instruments the writer reported as employed. The resulting figure given was so close to what my memory said amber's SG is, and the testing description so broad; I falsely assumed the jeweler used another standard gemologist tool. 

 

Now sent on the correct path, I simply looked up amber's Refractive Index, RI. There it is, the RI for amber is listed as 1.539 - 1.545. But wait, there's more! The RI for copal is 1.54! 

 

So, to make a positive and accurate diagnosis as to the ID of the piece - the acetone trial is the only method available to make the distinction, copal vs amber.

 

 

[sharktooth1996]

Folks, he actually used a refractometer as it turns out.

[snolly50]

11 minutes ago, sharktooth1996 said:

Folks, he actually used a refractometer as it turns out.

Yes, Tony's initial impression was of course correct. That device yields the RI he spoke of. However, the overlap of the RI between amber and copal still leaves the question, which is it? Place of origin would be a clue. I've got tons of copal from South America with beautiful insect inclusions. Being of that origin would raise  suspicion.  As I said many consider copal to be "young amber" and in terms of being attractive there is no apparent visual difference in the two. Amber does "win" in the sense of being much more ancient. This factor also obviously impacts the interest in the inclusions. Amber is more likely to contain plants and animals of interest to paleontology. 

[FrozenFlame]

Place of origin would really help, but if the static test is turning up negative (have you tried just getting a tiny piece of paper to zap?), the acetone is the last test, but it appears there is a chance it is copal at this point.