[1] Mondex also allowed for a full-card locking mechanism, usage with multiple currencies within a single card, and a certain degree of user anonymity.
Despite continuous investment from Mastercard, the Mondex scheme did not seem to catch on worldwide and the last place where it operated, Taiwan, had its cards disabled in 31 May 2008, being succeeded by a similar but more technologically advanced system, named Mastercard Cash, which utilized contactless operation, culminating in the TaiwanMoney Card.
[2] The Mondex scheme was invented in 1990 by Tim Jones and Graham Higgins of NatWest in the United Kingdom.
In March 1992 internal tests of the system, known at the time as 'Byte', started running at one of NatWest's major computer centres, Goodman's Fields in London.
[3] Development continued in secret until December 1993, when the system was publicly unveiled with an announcement that the Midland Bank (which had recently been acquired by HSBC) had joined the scheme as a 50/50 investment partner.
The public phase had required the development and manufacture of numerous merchant devices and smart cards, with BT, NatWest and the Midland Bank sponsoring and installing retail terminals at the car parks, payphones, buses and at merchants in the town, and issuing Mondex cards to residents.
Mondex launched in a number of markets during the 1990s, expanding from the original trial in Swindon to Hong Kong, New York and Guelph, Canada.
Throughout the late 90s and early 2000s trials continued to be executed throughout the world, with varying degrees of customer adoption and popularity.
In order to top-up their cards, users could use an ATM, go to a bank branch, or visit several stores and businesses with compatible hardware.
Depending on the country where the system was implemented, Mondex cards were accepted at a variety of businesses - supermarkets, department stores, public transport, taxis, car parks, vending machines, restaurants, cafés and many more.