The Maven ecosystem, with an emphasis on Maven Central, contains a plethora of toy-projects. This paper addresses this problem by formulating a core containing the pillars of the Maven ecosystem, such that it can be exploited for research concerning li- brary quality. The construction of said core is done by analyzing the availability, relevance and depen- dencies of packages in the Maven ecosystem. It involves answering questions regarding the distri- bution of library usages, the dependencies of popu- lar libraries and the effect of a usage threshold fil- tering mechanism. We found the popular libraries to be utilized to an incredible extend, while their less popular counterparts are seldom, if ever, used. Delving into the creation of a core reveals its non- trivial nature, requiring intricate knowledge of the Maven dependency mechanism and its accompany- ing tools to construct. This paper explores the com- plexities, nuances and considerations involved.