RARE VINTAGE 8K Solid Gold COIN. Miniature Gold coin Pope John Paul II – Special. 2 – Miniature Gold coins – Pope John Paul II – Holy Year 1983. 1 – Miniature Gold coins – Pope John XXIII. Note : STUNNING gold coin POPE John Paul II – Holy Year – 1983 & John XXIII – Historical Commemoration. The world’s smallest gold 8K coins. The measures of each Gold 8k coin : 1,1 cm (diameter) with a weigh from approximately 9/10 of a gr to 1.0 gr!! Belonging to my private collection.