I think it is detail we need to see

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To bring an etched mark up for photography, try rubbing a little talcum powder over it.
If you haven't got talc, cornflour or ground cinnamon would do.
Just something you can get to stay in the mark that will easily wash off.
I rather suspect the black marks that look a bit cat-like are just the way some canes which were added at one point to form part of the design, have ended up squidged on the base. It does not look deliberate and humans just have a habit of trying to make random images make sense. Hence all the "miraculous faces in toast" stuff.

It also helps a lot to tilt the flat base towards the light, so that the flat part reflects light off itself and reveals your slightly deeper talcum powdered marks clearly.