Three-quarters of the stamps ended up selling out in three hours.
The launch of a crypto postal stamp in Switzerland caused the website of the country's post office to crash.
Back in September, Swiss Post had announced that it planned to release a total of 175,000 stamps.
Each features a QR code that leads to a digital image — and a total of 13 designs in differing degrees of rarity are available.
Just 50 tokens have the rarest design.
The stamps were selling like hotcakes when they made their debut on Thursday morning — causing technical issues on Swiss Post's website.
Technicians were hurriedly working to iron out the faults.
Three-quarters of the stamps ended up selling out in three hours.
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Stamp Collecting Goes Digital
Although these stamps can be used to send post in the conventional way, they're clearly designed to be collectors' items.
A marketplace has been established to ensure that each digital image can be collected, exchanged and traded.
Several countries have issued stamps that double up as NFTs — bringing a popular past-time into the 21st century.
A spokesman for Swiss Post told the swissinfo.ch news agency that they didn't expect demand to be so high on the first day.
