I can help with hallmarking!!

[louisella76]

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

[SteveLAO]

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]

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]

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...

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]

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]

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]

Thanks so much Steve!!! Fantastic advice

[SteveLAO]

Pleasure! Many people struggle with all the many aspects of hallmarking, but I'll try to make it easy for you all

[LucyAlicia]

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]

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.