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SteveLAO
10-04-2013, 08:04 AM
Hello everyone, I'm Steve from the London Assay Office. If you are having difficulty over any aspects of hallmarking I'll jump in to help with your questions! I've been in the trade over 30 years, (over 12 years on the retail side and 11 years in manufacturing amongst other things!) so I think I can see both sides of the coin! Anyway, let's see if I can't help you all in the wonderful world of hallmarking!!

ps_bond
10-04-2013, 08:36 AM
Hi Steve - many thanks for joining.

Do you have a an idiots guide to hallmarking mokume gane? Obviously it's part of the mixed metals area; relatively easy for copper/silver (silver + metal) - although is that on its own hallnote, or can it be with other silver items?
And how on earth do you submit e.g. platinum/18k and how does that get marked?

Wallace
10-04-2013, 08:37 AM
Hi Steve,

Lovely to see you here too.

Kindest,

Wallace

Dennis
10-04-2013, 09:29 AM
Hi Steve,
Thank you for joining us on this side. You will be much valued. Dennis.

SteveLAO
10-04-2013, 09:36 AM
ps bond - as long as we can get an assay sample and there is sufficient room to get a hallmark on the precious metal bit then it's not too much of a problem.

Regarding mixed metal marking in general - items of mixed metals do need to be submitted on a separate hallnote, but the same type of mixed metals can go on the same note. For example, if you have two items of silver and copper, and one item of silver and gold, then the 2 items of silver and copper can go on one note, and the one item of silver and gold will need to go on another note.

Mixed metals are marked using the entire hallmark of the least precious metal, followed by a "part mark" which comprises the millessimal fineness mark (925 or 375 etc) and the optional traditional fineness symbol (lion passant for silver, crown for gold etc) for the other metals. The order of metal (least precious to precious) is silver, palladium, gold, platinum. If the "other" metal is not precious then the mark "+METAL" is used after the hallmark. and if possible also on the base metal part.

Remember with all mixed metal marking, it must be very obvious to the man in the street what the different metal parts are, and this is usually achieved by colour difference. Don't for example, make something of silver, white gold and platinum as the "man in the street" won't be able to tell the difference so it's unlikely that you'll be able to get it hallmarked.


Hi Steve - many thanks for joining.

Do you have a an idiots guide to hallmarking mokume gane? Obviously it's part of the mixed metals area; relatively easy for copper/silver (silver + metal) - although is that on its own hallnote, or can it be with other silver items?
And how on earth do you submit e.g. platinum/18k and how does that get marked?

ps_bond
10-04-2013, 09:53 AM
ps bond - as long as we can get an assay sample and there is sufficient room to get a hallmark on the precious metal bit then it's not too much of a problem.

Regarding mixed metal marking in general - items of mixed metals do need to be submitted on a separate hallnote, but the same type of mixed metals can go on the same note. For example, if you have two items of silver and copper, and one item of silver and gold, then the 2 items of silver and copper can go on one note, and the one item of silver and gold will need to go on another note.

Mixed metals are marked using the entire hallmark of the least precious metal, followed by a "part mark" which comprises the millessimal fineness mark (925 or 375 etc) and the optional traditional fineness symbol (lion passant for silver, crown for gold etc) for the other metals. The order of metal (least precious to precious) is silver, palladium, gold, platinum. If the "other" metal is not precious then the mark "+METAL" is used after the hallmark. and if possible also on the base metal part.

Remember with all mixed metal marking, it must be very obvious to the man in the street what the different metal parts are, and this is usually achieved by colour difference. Don't for example, make something of silver, white gold and platinum as the "man in the street" won't be able to tell the difference so it's unlikely that you'll be able to get it hallmarked.

Ah, so with the platinum/18k it would hallmarked as 18k followed by platinum, with no worries about having diluted the platinum purity by joining it to gold? I wonder how many metals I could get into the mix before we ran out of space for the hallmark; traditional marks on all... :D

I've seen silver/platinum mokume - the difference is perhaps best described as "quite subtle". ISTR seeing some of it where the silver had been etched, so the delineation was clearer but still the colours were very similar. 18k mixes still seem the easiest to deal with; there, I suppose it doesn't matter what colours I've used for one hallnote, so long as the entire thing is 18k.

Thanks Steve - most useful.

SteveLAO
10-04-2013, 10:12 AM
The other way to differentiate between metals, and used less often, is by texture which is how the silver/platinum mokume is often done, and which you spotted. The dilution of the platinum is not an issue unless its absolutely swimming in solder!!

caroleallen
10-04-2013, 04:28 PM
If I were to add some 18ct yellow gold to a 9ct white gold ring that has already been hallmarked, can I get it marked again?

lorraineflee
10-04-2013, 05:20 PM
HI Steve, nice to see you over here too!!

Lorraine

Keia
10-04-2013, 07:28 PM
Hello everyone, I'm Steve from the London Assay Office. If you are having difficulty over any aspects of hallmarking I'll jump in to help with your questions! I've been in the trade over 30 years, (over 12 years on the retail side and 11 years in manufacturing amongst other things!) so I think I can see both sides of the coin! Anyway, let's see if I can't help you all in the wonderful world of hallmarking!!

Really nice to have you here :~:

louisella76
10-04-2013, 09:05 PM
Hello and welcome, I'm venturing into registering with the LAO so it will be interesting to read your posts :)

SteveLAO
11-04-2013, 08:03 AM
Hi Caroleallan - Yes you can! Actually you are obliged to, as you are not allowed to make any addition to an already hallmarked item unless it is sent back to the assay office for approval. In this case you would send the item back to the assay office and they will put the 18ct "part mark" on it. It's best to send it back to the assay office who applied the original mark.



If I were to add some 18ct yellow gold to a 9ct white gold ring that has already been hallmarked, can I get it marked again?

SteveLAO
11-04-2013, 08:05 AM
Hi louisella 76 - Thanks for your welcome, and looking forward to welcoming you to LAO.


Hello and welcome, I'm venturing into registering with the LAO so it will be interesting to read your posts :)

SteveLAO
11-04-2013, 08:21 AM
4623

Attached should be an image as an example. This was taken from an item that was made of silver, 18ct yellow gold and copper. The image shows the full mark for silver, the part mark for 18ct and METAL for the copper




Ah, so with the platinum/18k it would hallmarked as 18k followed by platinum, with no worries about having diluted the platinum purity by joining it to gold? I wonder how many metals I could get into the mix before we ran out of space for the hallmark; traditional marks on all... :D

I've seen silver/platinum mokume - the difference is perhaps best described as "quite subtle". ISTR seeing some of it where the silver had been etched, so the delineation was clearer but still the colours were very similar. 18k mixes still seem the easiest to deal with; there, I suppose it doesn't matter what colours I've used for one hallnote, so long as the entire thing is 18k.

Thanks Steve - most useful.

LucyAlicia
22-04-2013, 11:33 AM
Hi Steve, great to have you here!

I'm going to have some sterling silver items (rings, pendants, earrings etc) plated in 22ct gold and some in black rhodium - probably 2 microns thick. Is there a min/max thickness in microns of plating in order to have these hallmarked with the plated metal as well as the silver? Also, as these will be finished items, is there any danger that they will get scratched during the hallmarking, either when finding out the materials or when using a punch? I heard there was another way other than scraping off a piece of the item?

Also, if I have all sorts of jewellery, would I need to buy a straight and cranked punch for my sponsor's mark, or is it possible to get away with one type?

Sorry for the bombardment! Any advice greatly appreciated!

Thanks,
Lucy

SteveLAO
23-04-2013, 08:39 AM
No problem plating with black rhodium or 22ct on silver. The maximum permitted plating thickness is 2 microns. It's difficult to tell until we have the items in front of us, but we might have to remove a tiny bit of the plating in order to test underneath, but it'll be in an inconspicuous area. We usually test using xray these days which is non destructive but it is only surface testing. Sometimes it can read through the plating but sometimes it can't! There is no more or less danger if the items are finished, but having said that, we do handle finished items differently - often with cotton gloves - so we will be careful with your items! Remember though that only silver items over 7.78g are required to be hallmarked by law. Under that weight they are regarded as "non liable" which means they don;t need to be marked by law.
Regarding punches - straight punches are great if you have a clear line of sight, and are generally used for marking silverware and not jewellery. The cranked or swan neck punch gets in all those hard to reach ares, like the inside of ring shanks and bangles, where a straight punch can't reach. So in summary, the swan neck can do want a straight punch can do, but a straight punch has limited access when marking jewellery, so if you're only doing jewellery then the swan neck is the one to have.

LucyAlicia
23-04-2013, 02:10 PM
Thanks so much Steve!!! Fantastic advice :)

SteveLAO
24-04-2013, 01:40 PM
Pleasure! Many people struggle with all the many aspects of hallmarking, but I'll try to make it easy for you all :)

LucyAlicia
24-06-2013, 12:23 PM
Hi Steve,

I've registered and got my swan neck sponsor's mark punch all sorted - very exciting! I just have one more question if that's ok - I've got the small size M 0.5mm punch - one of your colleagues told me that I can plate up to 2 microns thick on top of silver after hallmarking, as well as before. My question is, if I have all my pieces hallmarked while they are silver alone (perhaps easier as I can retouch them if needs be before I send for plating), would plating of 2 microns thick fill in that small hallmark do you think? Just trying to work out the best process for everything!!

Thanks again for your help,
Lucy

SteveLAO
24-06-2013, 12:31 PM
Best to have it marked first and then plate. 2 microns won't really affect the definition of the mark even in the small sizes but there is always the risk of the plating cracking if you plate first and mark second, and of course if you're going to laser mark then the laser will burn through the plating.

LucyAlicia
24-06-2013, 12:50 PM
Hugely helpful - thanks Steve