Mobius

This would be a Queen Victoria duty mark - after rotating the mark it is super obvious.

Here is a reference example

@Carptastic1 - there is another mark on the right that we cannot see - this is the maker's mark - if you can ahow a better photo of that we might be able to work out who the maker is.

Yeah, we love it.

Sadly, folk after help with hallmarks are often “one post wonders”, and often don’t ever say thanks after others have given them information. 

Yes, but I am not disappointed. Any unseen hallmark is for me a good detective exercise and I really enjoy searching informations.
Also, I am sure that the results are useful for another forum members, so....life is good!🤗

It is wise to have both metals in stack as principal. Some people are stacking as well platinum/palladium, but these are too risky and speculative for my taste.
Gold and silver passed the test of time and their value was only growing steady on long term, so I have appetite only for them.
I try all the time to have @50%-50% value, just in case, to be prepared...
We can see charts from the past, we can compare and extract "facts" from them. So far, gold did a little better than silver and I can not argue about.
But the charts for future we can only imagine, so we don't really know which one will perform better in the years to come. Maybe silver, maybe gold. Maybe lithium or metallic sodium. Maybe bismuth and chrome. We don't really know.
Everyone is free to invest in what he/she want and like. It is not a competition between us, it is only a competition with our life time. I'd like to accumulate enough until I will die for my descendants. 
Yes, beans and alcohol performed better than silver and gold in the last 10yrs. But can I leave as an inheritance for my children and grandchildren 100 boxes with beans and 50 boxes with vodka? I would be ashamed by myself! So...I will continue with gold and silver.
Happy stacking, everyone!🤗

Perth Mint. If you ever want to to talk PM’s PMs just PM me. 

Hey, @Stevestreasures!
You are alright, mate?
 

Hi, @Stevestreasures.
@Mobius is right, your plates are french, indeed, which explain the purity of .950.
The hallmarks are from 18th century, before 1797, so very probably arrived in America during the french colonial period. It is almost impossible now to know the name of the silversmith who made them, the database for that period is very thin. Also, the maker's mark - fleur de lys crowned had when new stamped around the initials of the tax payer maker, but can not be read now unfortunately, are too rubbed.
Anyway, what I can tell you for sure is:
1. It is .950 silver (the cockerel with little number 1, used for silver 1st finesse).
2. The work for your plates started in Rouen between 1775-1781: ("B" letter is mark of charge for Rouen and was applied after the maker's mark on the object under construction, but before the stamping of the mark of "maison commune".) The font of the "B" letter from your plate was used between 1775-1781.
3. The mark of discharge was applied in 1789 by assay office ( "maison commune").
So, even the work for these objects started @1780, couldn't beeen finished and sold before applying the discharge stamp in 1789. I am very sure that The Anglo-French War, followed by a deep financial crisis and by French Revolution slowed down the work in the silversmith's workshop.
I hope this helps. Very nice pieces!🤗
Cheers!
Stefan.

 
 

The makers mark is impossible to make out but the other marks look French to me. The style is Georgian (1820 ish) but could obviously have been made later. 
@stefffana might be able to shed more light on it.

I have a few of these ingots.
What I've noticed is that the 1977 dated ingots are Britannia silver and the other dates, i.e. 1976, 1979 etc. are sterling silver.
I guess it was deemed appropriate to use Britannia silver for the Jubilee year? Interesting, and something new to discover.
 

Oh my!
I had it as sterling...I must check them all now! 
Learn something every day....I didn't know they made ingots in 958 👍

@Mobius, your turn now, mate!😘

Time for conspiracy theories, guys!
 

 
John Dee was astrological and scientific advisor of Queen Elizabeth I. His work and studies in alchemy and mystical/paranormal/spiritual/parapsychology and other dirty minds stuffs for that era are very well know, but the final result of this work is covered in fog and clouds. We don't know if he managed to learn how to reincarnate himself. Maybe he did it!
In 1577 he started a diary about these studies. He loved from all his heart his queen and promised her that he will do something remarkable for her memory in the years will come. The diary is not very clear, but he mentioned there about Britannia and about the purity of the chemical element named "argentum".
After exactly 400yrs, an ingot made from Britannia "argentum" is made to celebrate who? The second Queen Elizabeth and it is signed JD. This JD maker made only these ingots and disappeared probably for another 400yrs.
John Dee (in the flesh of one of his multiples reincarnations) did exactly what he promised!
 

 
 

Well, you see Sheffield and JD on some silver and you think James Dixon.
But he died in 1852.

Or did he....
 

Yep, according to Silver Makers Marks, JD is err... JD! Big help.
It's too modern for any of my reference books too I'm afraid.

Yep, according to Silver Makers Marks, JD is err... JD! Big help.
It's too modern for any of my reference books too I'm afraid.

Oh I'm so pleased and indebted. I tried I j and l as first letter and was totally frustrated.
thankyou all so much
Kevin

I totally agree with @Mobius.
1836
Maker's mark is in accordance with the year 1836. From 1837 they changed the shape and font.

Hi, 
The maker is/are Samuel Hayne & Dudley Cater. Year is 1836.
Mobius

@stefffana @Mobius

Hi, 
The maker is/are Samuel Hayne & Dudley Cater. Year is 1836.
Mobius

May thanks for your replies

The maker is probably Joseph Mappin, but the date is more difficult, if it is Joseph Mappin, it's possibly from around the 1840's, before the formation of Mappin Brothers (and later Mappin and Webb).
Hope this helps.
 

Hi,
These marks are 'pseudo-hallmarks', meant to resemble real hallmarks at a glance, which unfortunately makes your sugar tongues electro-plated and not silver.
Mobius.

These marks were listed on silvercollection.it as Mappin 
There is also some discussion on another website - not in English
https://www.precisensan.com/antikforum/showthread.php?11276-Märkliga-stämplar-på-okänt-material