The year 2021 marks the 100th anniversary of the death of Jan Janský - the world-famous Czech physician and scientist. A half-ounce gold medal of the Czech Mint was created on this occasion. It is part of a free cycle of the most beautiful unrealised designs entered into the Czech National Bank's competitions.

Jan Janský, as a psychiatrist and neurologist, was of the opinion that mental illnesses have physical causes, which he sought in the blood of his patients. In the course of several years of research, he came to the conclusion that there was no relationship between blood and mental health, but he noticed that human blood could be divided into four groups according to certain differences in the properties of blood cells. He published his findings in 1907 and did not study them further. Unfortunately, he had no idea what a revolutionary discovery it was. At that time, three-quarters of patients died during transfusions because of blood clotting from an unsuitable donor. If a doctor had been able to determine what kind of blood they should receive, it could have saved countless lives... Fortunately, Jan Janský was not the only one who was working on this issue. At the time of his research, he had no idea that the pathologist Karl Landsteiner was involved in blood clotting in Austria. He had already discovered the existence of the basic blood groups in 1901, for which he received the Nobel Prize in 1930. However, the Austrian professor described only three groups - A, B and 0 - and the fourth group AB remained a Czech discovery, which was recognised by the whole world. The importance of our compatriot is still commemorated by the Janský Medals, awarded by the Red Cross to selfless blood donors.

The design of the gold commemorative coin was based on the artwork of the medal maker Mgr. Petr Horák. The obverse side bears a charismatic portrait of Jan Janský, accompanied by his name, anniversary dates, a drop of blood and the Aesculapius staff. The reverse side presents the circulatory system of the human body and a diagram showing the compatibility of the four blood groups.

The schedule of issuance has only 99 pieces. In addition, each medal is hand-numbered on the edge.