I modelled this coin tray using Plasticity3D and Affinity Designer. 

To create the two-colour appearance I made a material change using PrusaSlicer for the last two layers in height from black PLA+ to Silk Gold. You could make the colours anything you like - this is just what I chose.

Here's a youTube clipping demonstrating the layer-height material change technique: 

I've added the gCode I made to this project so you can just use that if you like and your printer will pause for you to perform the filament change. 

Good luck and happy printing!