areas as islands consisting of Au films of roughly 4 to 8 monolayers thickness with immersed larger Au clusters. The Au films show areas of crystalline structure with essentially two different lattice plane orientations as shown in the circled areas in Fig. \[expfig1\](c). A close analysis of the properties of the Au films including a holographic determination of its thickness is given is Sec. \[sectiondynamics\]. We arrive at the conclusion that the islands are formed by coalescing small clusters with diameters of $< 2$ nm.

Since the observed island formation was unexpected on the amorphous substrate, no monitoring of the dynamics of the formation of the islands—as desirable—was done. Awaiting the preparation of new samples, which are needed for the observation of the formation process, the present paper aims to give a state-of-the-art analysis of the system at hand. Based on these findings the time-analysis will be performed once new samples are available.

Outline of the paper {#outline-of-the-paper .unnumbered}
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In Sec. \[sectionmethods\] we describe the experimental \[sample preparation and TEM\] as well as theoretical \[density functional theory (DFT) and Monte-Carlo (MC) simulations\] methods applied.

Since the main trade-off of the amorphous substrate is its less well defined surface we 