One characteristic of science centers and science museums is that they communicate scientific findings by presenting real scientific objects. In particular, science museums focus on the historical context of scientific discoveries by displaying authentic objects, defined as original objects that once served a science-related, real-world purpose and bear some significance for the history of science. However, almost nothing is known about the respective role of authentic objects. By displaying a set of objects either as originals or replicas in a large museum of the history of science and technology, we examined the relevance of authentic objects for museum visitors. An extensive set of interviews unveiled four dimensions of authenticity, interestingly not only connected with the historical significance of the objects but also with their science-related functionality. Furthermore, it revealed a multitude of criteria for the evaluation of objects that were mostly independent of authenticity but instead referred to the objects' provision of insights into scientific and technological principles. Thus, the study shows that it should be of great importance to complement authentic objects with features that provide additional science-related information. How this connection can be most successful requires further research.