I've used the peroxide method for years. Bill uses 12% strength, but you can buy a weaker mix, I use 3%. That means the reaction isn't as fast and you have a bit of time to watch the progress and judge when you're happy it's done. Some stamps take a little longer than others. As Bill noted, this is only for the Line Engraved stamps.

He describes everything in layman's terms. You can see his genuine enthusiasm and love for his craft. Can listen to his narration all day.

It was awesome witnessing this rare scene, and even better to review from an #philately episode. 🙌

This was a rollercoaster episode for my anxiety.  Well done Bill and Graham.

A superb vignette. I admit to being very apprehensive watching Mr. Barrell subject Penny Blacks,  182 years old, to hydrogen peroxide, but he is obviously a real pro.

Fascinating detective work by Bill

Have not seen or heard of that peroxide trick. Wow. He knows what he is doing. Quality detective work right there! Great video Graham!

Excellent video, and great information from a line engrave stamp expert.

Be very very careful with the use of Hydrogen Peroxide. on postage stamps.
I have read about some concerns regarding the long terms effect on the strength of the paper.
So be mindful of Bill's advice to limit the exposure to 30 seconds or less.  And be sure of the inks on the stamps you are cleaning!

There is also a viewpoint that the discolouration or sulphurization of he stamp reflects part of it's 182 year journey.  Our role as collectors is to be careful custodians of the material for the relatively brief period that we own them!

What an amazing video ...never knew anything about this !!!!!

A very nice educative video on how to spot alterations to a PB cover. Many thanks to Bill for shining light on this. 👍👍👍

Loved the forensic work. Putting a row of four Penny Blacks into water was scary enough, then putting them into a bath of Hydrogen Peroxide was crazy, loved the result. Great video Graham.

Incredibly interesting and informative!  Witnessing the detective work of an expert philatelist was so eye opening and educational.  Thanks Bill and Graham.

Who would have thought a video on stamps would have my heart racing from nerves. All of the things he did to those penny blacks! Obviously though, an experienced professional. I learned a lot from this today!

The way he manipulates the stamps and the cover almost gave me a heart attack 😂 il do it so softly

Well done Bill!!  So interesting to watch.

Brilliant video. Bill is such a great dealer and person.

Thank you so much bill what a fantastic fellow , I ve learned so much .

I am visiting the UK right now and wished I’d have been able to visit the show. I’ve done business as a client (in Australia) with Bill and his staff and its good to actually see him in the flesh. As to other matters: I purchased a embossed issue of 1848-55 on cover, and like the wrapper in the video I think mine (and others have told me so) is not tied and contrived - original stamps and original cover later combined. I have kept this item as a warning to myself.

It was really a great episode, Graham! When bill got the Hydrozen Peroxide, my heartbeat gone up 😂
But I'm mostly amazed just how he predicted that the maltese cross was red, not brown. However, a great episode, enjoyed a lot 😄

What a fine person Bill is, and what a treat to learn so much in such a short time from some one so knowledgeable. Well done, again.