The Rand currency was introduced in the then Union of South Africa on 14 February 1961, shortly before the establishment of the Republic on 31 May 1961. It had a two-and-a-half-cent denomination, replacing the earlier threepence coin which had the same mass and dimensions. The new coins were 50% silver and retained the reverse design of the threepence created in 1925 by George Kruger Gray, featuring a Protea flower.
The 2 1/2 cents circulating denomination was short-lived though, and was discontinued after 1964 in favour of a new 2 cents coin.
In 1997, the South African Mint started issuing Non-Circulating Legal Tender (NCLT) 2 1/2 cents coins in a new series known - from the flower featuring on the coin - as the Protea coin series; the flower is now on the obverse, and the reverse designs celebrate various aspects of South African heritage and nature. The coins are usually issued in a "Crown and tickey" set (tickey being the nickname of the coin), together with a Crown piece (one ounce silver), with new themes every year.
The composition is Sterling Silver - 92.% silver alloyed with 7.5% copper.
This coin is part of the 2020 Crown and Tickey series of coins featuring a South African invention that has revolutionised cataract surgery. The retinal cryoprobe was developed by South African ophthalmologist and inventor, Selig Percy Amoils, at the Baragwanath Hospital in Soweto, South Africa.
The cryoprobe is a pen-like instrument that delivers extremely cold liquid gas, with precision and accuracy. The cryoprobe is inserted into a cut in the eye to deliver a liquid gas , which freezes to a cataract. The cataract (or other unwanted tissue) can then be removed with no risk of destroying healthy adjacent tissue.
It has since found applications in the field of general as well as veterinary medicine. | 
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