The Coin Cabinet provides broad glimpse and a powerful reflection of the Joanneun coin collection in its entirety and has also been inspired by the castle location in the very hear of Schloss Eggenberg. The platform for the display is in two rooms both in the oldest part of the castle dating from the second half of the 15th century and named in Latin documentary sources as Castrum Eckenperg. This was the original structure in the princely residence.

The ”Balthasar Eggenberger” Room – named after its builder, the richest citizen of Graz in the late middle ages – provides an insight into the life of this financial tycoon, who laid the foundations for the rise of the House of Eggenberg. During the 1450s Balthasar became financier to Emperor Friedrich III and was appointed Master of the Graz Mint. His contemporary Jakob von Unrest describes these times in his Chronicle of Austria: ”The emperor permitted bad coins to be struck and these were called “schinderlings”. Anyone who had a lot of old copper kettles could strike much better ones. He permitted the minting of these coins ... to a citizen of Graz named Eggenberg. He had the lease of the imperial mint. The controllers, mint masters and mint journeymen became great and wealthy men.” The author described the so-called Schinderling period, when poor quality penny coins of copper were in circulation and resulted in a spectacular monetary crisis that caused considerable harm both to the people and to the economy in the Austrian lands.

Hans Ulrich von Eggenberg was the great-grandson of Balthasar and the prime minister of Emperor Ferdinand II. This was the Eggenberger, under whom the construction of the princely residence was begun in 1625. This remarkable and highly educated man who rose to be one of the most influential princes in the Holy Roman Empire within the course of a few decades lends his aura to the atmosphere of the second exhibition room. The coins on display in this room provide an account of the coins produced and those in circulation in Styria from antiquity through until the end of the 18th century. Impressive treasure finds and selected coins that have been found as single pieces illustrate the position of Styria in the interregional monetary systems since Celtic times. Selected coins from the Graz mint also show the kind of work that was done at this centre for the striking of coins and minting of money and that was in operation from about 1215 for about 500 years until its closure in 1772 by the Empress Maria Theresa.