Gold Sov thickness

[TopHatsTales]

I recently purchased some gold sov's from a very well know online retailer, based in the midlands.

All weigh 7.98g and are 22.05mm (+/-.05mm) diameter. Great.

Using a vernier they come out too thick, but the rim is thicker, so i purchased a micrometer. Using the micrometer they still come out too thick, at about 1.75mm

The spindle of the micrometer is too large though, so always sits on part of the raised surface (cameo etc) and not the flat of both (or even either) face.

Looked at a few micrometers and they all have 6.35mm diameter spindles....like mine.

I purchased 5 Sov's, got 2* QE2's, 2* George V's and an Edward VII. None have mint marks.

Considering where i got them from and after weighing and checking the diameter with a vernier i was totally happy. Expected checking the thickness with the micrometer to be a formality, but not so confident now, as thickness is the most common way to fake them.

Some assistance requested please....

[Kman]

If you bought from a reputable dealer (Atkinsons?) they will be fine

 

[sovereignsteve]

Thickness is a difficult one due to the variation of high and low points on a sovereign. This is because of the difficulty making the dies with a consistent blend of high and low. Some have thicker rims than others but in a perfect uncirculated condition, it is usually the rim that is the thickest part, especially in very modern ones. The dimensions that can't and don't vary are the diameter and weight, the thicknes does.

In fact, it is very difficult to find any two sources of information on this subject to agree.

Chards: 1.0 - 1.4 mm
Goldsovereignexpert: 1.0 - 1.69
Wiki:  1.52 mm

Yours at 1.75 mm should be fine, it may well be your gauge is reading slightly high at the lower end, where any imprecision will be more evident. Either that or your supplier has been duped with a batch of consistently large sized fakes, from 1900 - present day. Highly unlikely.

 

[TopHatsTales]

Cheers guys.

What makes you think it came from them Kman 

Other threads i have read suggest that at 20% over spec (1.52mm?) is fake.

I did open the micrometer out to 2.0mm and measured with the vernier...at 2.0mm

[sovereignsteve]

3 minutes ago, TopHatsTales said:

What makes you think it came from them Kman 

I would say it's as good a guess as any

[danmc82]

Is it possible to do a gravity test with Sovereigns?

[Coincollector]

From my experience most sovereigns should have a thickness of 1.52mm. However I have noticed that Sovereigns from 2013 onwards. Have a higher rim than before, making there thickness around 1.7mm. The rim on these modern sovereigns is noticably thicker when holding the coin between finger and thumb. Measuring a 2015 and 2016 the thickness on the rim comes out at 1.68mm has any one else noticed this with modern sovereigns?

Hope this helps.

[Pete]

If 2 coins have the same weight and diameter then their specific gravities are in direct proportion to thickness.

Comparing 1.75mm vs 1.52 mm this is a difference of 15% so if your micrometer readings are indeed accurate then I would start to be concerned.
I was sold a "jeweller's copy" sovereign from a VERY reputable supplier - one that has a quick turnaround !
Fortunately I made all the measurements and had a no quibble replacement including return shipping but it had obviously passed through the net so to speak.
It was slightly too thick which was the trigger to make more measurements and from SG I confirmed that it was 18 carat not 22.

Since you are measuring a mixture of sovs, I suspect your micrometer is out of calibration, not zeroed correctly or there is a systemic error in your measurement method suggesting the coins are indeed genuine but I would want to know why the readings are high. If you have a proper feeler gauge ( used for setting spark plugs etc. ) see if your micrometer reads accurately and see what it reads when the gap is fully closed.

Measuring thickness is tricky due to cameo and rim so I suggest for piece of mind you attempt to measure as best you can specific gravity on all coins and see if there is much variation.

[sovereignsteve]

3 hours ago, Coincollector said:

From my experience most sovereigns should have a thickness of 1.52mm. However I have noticed that Sovereigns from 2013 onwards. Have a higher rim than before, making there thickness around 1.7mm. The rim on these modern sovereigns is noticably thicker when holding the coin between finger and thumb. Measuring a 2015 and 2016 the thickness on the rim comes out at 1.68mm has any one else noticed this with modern sovereigns

Yes also George v sovs often have a thick rim due to the bust profile being shallow.