Hello dear friends, first, I'll introduce myself, my name is Luis Quintero, I'm a Venezuelan currently living in Dallas, interested since I was a little child in coins and banknotes.

I've been doing some research about the Venezuela's relationship with Great Britain mints and I just find out some proofs minted by "King's Norton Mint" and doing some research, I could not find too much information about this mint, only what Wikipedia says or mention in some articles or auctions. 
I've realized that there are some archives about it, but I coudn't find information about this archives. 
Is there any book or releated article about it?
Thanks.

Welcome to the ANA! Sorry, I can't really help you, but hopefully someone else can, have a nice day!

First off, welcome to the site, and we would be honored to have you join our ranks!  Thanks for asking!  I am not sure, but the ANA has a library of around 128,000 physical books that you have free access too, so I would imagine that one of them contains the information you need.If you go to LIBRARY on the top bar of the website, then click on CATALOGUE, they have a wonderful search feature.  Other than that, I am afraid I cannot be of assistance... I wish you luck on your journey! Playing the sleuth is half the fun of numismatics!  Cheers, NM

Welcome to our little coin community here on the ANA website! An as NumisMaster said, you can check out books from the ANA library through their website. But, it is closed right now, so you will have to wait a bit until it reopens. If I remember correctly, you can order scans of certain pages that will be sent to you digitally, for a small fee

I have studied the mints from Britain starting with the Soho mint. This became the Birmingham mint under Mr .Heaton. Your mint was taken over by the New Birmingham mint. The Norton  had mostly machinery parts but did make coins for various countries. Ireland being one. Those coins I believe I have.I would have to serch. They made planchets for other countrys. My expertise goes to the Soho up to the New Birmingham mint. Sorry. But those three mints are the ones I collect from . Like i said the New Birmingham mint took over the Norton mint. welcome to the ANA.

Mike B. is correct. They supplied the planchets, not only for Britain but Ireland as well. I know this because I lost in a Heritage auction bidding war for a 1911 Farthing Specimen Proof a while back . Closed way over my budget but wow was that exciting! The pedigree coins always carry a very healthy premium when they appear, which is not that often on the earlier strikes.

Thanks for your help guys, I really appreciate it.
Already checked ANA Library, but there is nothing specific about the King's norton mint. 
I know the part about them being taken by Birmingham mint, but in the years when they made the Venezuelan proofs that I show in the picture above, the were subcontracted by Royal Mint I really don't know why, because Royal Mint was striking those coins for Venezuela already. 

I remember reading somewhere (I don't recall the source offhand) that the Royal Mint would subcontract some work to the King's Norton Mint during periods when they were over capacity and couldn't meet demand. This was particularly the case during the late 1960s, as they were ramping up production for the switch to decimal coinage in the U.K.

I own a 1968 Ireland penny with King's Norton Mint provenance. It received the 'specimen' classification from PCGS. No Irish specimen sets were struck for that year, but 30,000,000 circulation strike Irish pennies were produced. My theory is that the Royal Mint subcontracted (or at least explored the idea of doing so) some of the Irish production for that year to the King's Norton Mint, and my specimen penny is from a small group that were struck to demonstrate that they could produce satisfactory coins.

Welcome. Have you tried the Newman Numismatic Portal, https://nnp.wustl.edu/library/dictionary