That's how philatelists around the world described Spink's sale of the incredible Chartwell Collection, one of the most important stamp collections in history, amassed by the late businessman and philanthropist Sir Cyril Humphrey Cripps.
Spink's Chairman, Olivier Stocker told UK newspaper the Daily Mail that this sale has been "without a shadow of a doubt, one of the biggest 'wow' moments we've ever experienced."
I've been on the saleroom floor for both days of the sale. (You can see it in the below photograph.) And it's been a privilege to witness philatelic history first hand...
You might think that "witnessing history" is an exaggeration. But day one of the sale has already seen a new World Record price for a stamp auctioned in the UK.
The prospect of a 9.72% per annum wasn’t enough to persuade Sir Cyril Humphrey Cripps to part with his legendary Mauritius 'Post Office' 2d blue stamp. Today, it is the most valuable stamp ever auctioned in the UK
The piece in question was the legendary Mauritius 'Post Office' 2d blue - probably the most beautifully preserved example of its kind (of only 27 known examples).
It's been called the "lightest cancelled" of the Mauritius Post Office issues, featuring a neat cancel at the bottom left-hand corner.
To give you an idea of how important this stamp was to Sir Humphrey, five days after he originally bought the stamp for £29,000 in 1972 somebody else offered him £39,000 to buy it.
Sir Humphrey turned the offer down.
If you're unfamiliar with philately, it may surprise you to learn that this stamp has been expertly restored in much the same way as a classic car or piece of antique furniture.
Needless to say, the excitement in the room was tangible and - as I've said before - never underestimate how this adrenaline can push up an object's price.
The £400,000-500,000 estimate could barely contain the Mauritius 'Post Office' 2d blue. In the end, it sold for £1.08m, the most expensive stamp ever auctioned in a UK saleroom.
Spink’s London experts preside over the incredible Chartwell Collection sale – the philatelic auction of a lifetime
So, that's another one for the philatelic history books.
As if that isn't enough, the sale also saw a new World Record price for a British Virgin Islands stamp - follow the link to read our full report.
What's more, the Mauritius and Virgin Islands stamps each went to the same unidentified telephone bidder. I reckon that somebody is buying the world's rarest stamps to build a 'string of pearls' collection...
This would certainly fit in with recent trends in the collectibles markets, where wealthy "Medici buyers" are devoting themselves to amassing new world-class collections.
All the best, until next time
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