Pearl Necklace Silver Clasp - Good Eyes Needed Please!

[englishladyfromkent]

Greetings to all -

This was my aunts necklace. I believe these are 'real' pearls although what type I have no clue. The clasp is silver with some stamps so I'm posting in the European section since I am in the UK, although the provenance of the necklace could be anywhere.

I have been googling trying to learn about pearls but there seems a great deal of mis-information out there. These do feel gritty when rubbed gently against a tooth and I have examined the bead holes really carefully with a loupe - no flaking or loss of nacre there. And there are knots in between each pearl.

It is clear to me that these are not costume jewellery - not glass or plastic either. Neither are they Roman pearls. All the tests suggested online involve destruction which I do not want to do - so I am hoping for some guidance here on the tiny marks on the silver clasp.

I am posting an image of the necklace, the clasp (of a type I have never seen before) and the tiny marks on the tongue part of the clasp. On the back of that tiny tongue are two numbers as you see. One is 750 and upside down against it is 900.

The writing on the other side of that tongue are the critical marks. But since the mark is on the thumb press part, some of the first two letters have not come out clearly.

The final picture is the clearest of this mark I could get. I took 97 pictures and this was the only one in which I could read more than the number. I think the letters are MH but am not really certain. Then there is what looks like an open double size clam shell mark (with nothing inside it) and then the number 750 again. Sometimes I think there are two other marks in between but I just cant see what they are.

This one really has me confused as I have never even heard of a country which used 750 as its silver fineness mark. And if it really is 750 then why is it stamped 900 upside down above the 750?

Sorry - so many questions. This necklace was not boxed but was very carefully packed and padded. I was lucky enough to inherit several boxes of jewellery and this is another of those pieces.

The necklace itself is carefully made, and is just over 20" long and made up of 'pearls' which are 8mms round. I have looked at each of them in daylight with a jewellers loupe and none has any scratches or marks. One of the tests suggested online is rubbing two of them together. Apparently any scratches left will simply wipe off. Have to say I am not convinced on this test and have not done it.

I've only just moved here and do not know any bench jewellers or gemologists. I think it is most unlikely any dentist would x ray them for me and even if they did, I would be unsure as to what to expect to see.

Really appreciate some input on this one and thanks in advance to anyone who can help in any way.

Kind regards


Julie

[JLDoggett]

It appears to be marked for 18kt white gold, and coin silver, a very odd combination. Are both parts maked the same? I can not make out the maker's mark.

[englishladyfromkent]

Hello and thanks for your input.

It is only the tongue part of the clasp which is marked and yes, that is marked both on the front (with the thumb press) and on the back.

The back which is fairly easy to see has the 750 mark but also the figure 900 lightly impressed upside down tight up against the 750 mark.

The front of the thumb press has most marks. Looking today again in natural light I see there are four distinct marks.

From left to right they are:

1. A rectangle pushed to the right making a trapezoid shape (?). Within that mark are two letters. The first is clearly M. Now I look at it again the second letter looks like an S.

2. Next is an oval mark with what I think is the letter 5 beside a cloud shaped imprint.

3. After that is again the number 750 (which is also marked on the back of the tongue).

4 This looks like a shield shape with the base sides being curved downwards both sides.


I am going to go outside and try to get better shots of these marks. I will report back later once I have looked at them and picked the best.


Thanks for your input again - it is really much appreciated.

Kind regards


Julie

[englishladyfromkent]

Just a little to add after further research: I have looked at the clamshell mark with the M inside on 'Mikimoto' pearls and it does not look like the mark on these.

I've been researching white gold marks and 750 was the export mark for white 18k gold from Japan.

I've also found out that platinum is sometimes marked 900.

A reputable jewellery site states that white gold in jewellery was first made fashionable in the 1920's as a more affordable alternative to platinum and is tarnish free. The clasp on this string of pearls has not built up any tarnish at all.

Going by age and generations of these, I would say that this string of pearl is older than the 1920's but cant tell for sure.

Hope this info is of use to someone who knows about these metals.

Kind regards

Julie

[englishladyfromkent]

After many hours of research online, I think I have stumbled upon the answer to the dual marking of the clasp of this necklace.

As someone said earlier, it is 18k white gold18K and the rest of the alloy is made up with platinum - hence the mark of 750 with 900 above it. This is normal practice or was at the start of the 20th century.

I'm satisfied that I know that these are 'real' pearls as I thought, they are professionally strung and obviously on their original string.

Now I have to find out what type of pearls they are ! Anyone know of a pearl expert by any chance ?

Thanks to everyone who helped me reach this conclusion and big hello to dognose for allowing me to post this information. I would move it if I knew how to a more appropriate section of the forum, but will leave that to admin with thanks.

Kind regards


Julie

[JohnQ]

Hello, I am an estate Jewelry dealer in California, I specialize in natural pearls and from the look of the photograph, these are most likely cultured pearls. For verification you can send them to a local gem lab for certification. If you're in USA I recommend EGL as they have the best rates and quick turn around times.
Or, if you're just curious and don't care if they are or are not natural, take them to your dentist and ask for a quick X-ray, post a scan of the X-ray and I'll tell you immediately if they're natural or cultured, saves you the cost of the cert since most x-rays are about $10-$15 per at the dentist.

[oel]

Hello JohnQ,

Welcome to the forum and thanks for the tip on pearls.

Regards,

Oel

[LucieK]

Thanks for sharing all these detailed updates and photos—you’ve clearly put a lot of thoughtful research into this, and it's been fascinating to follow along. I completely understand your hesitation about visiting a dentist for an X-ray—it's definitely an unconventional route, and without prior experience or a jeweler to guide you, it may not offer the clarity you need.

That said, you're absolutely on the right track by examining the clasp markings. The presence of both 750 and 900 is unusual but not unheard of, especially in older jewelry where platinum and gold were occasionally alloyed together, as you’ve discovered. Your detective work on white gold and its history, particularly its rise in the 1920s, is also spot on and helps narrow the age window.

If you're still looking to confirm the pearl type, you might try reaching out to a local auction house or antique jeweler—many have in-house gemologists or can refer you to someone reputable nearby. In the meantime, enjoy wearing them! Their elegance and craftsmanship already tell a wonderful story, and your care in uncovering their history makes them even more special.If you need i know one in here in France specialised in [commercial link removed by moderator]