My first photomicrograph is at 200X; the next two were made at 500X. It was difficult to match the colors between the first image and the next two. The copper rich phase was already reddish in the first image, but at 500X that's about as red as I can make it without really distorting the color rendition.
You may also want to look up where copper and silver lie in the galvanic series.
See if you can check my estimate of the overall composition by considering the area fraction of the two different microconstituents and the area fraction of the two principal phases in these microconstuents. Area fractions and volume fractions are equivalent. To get weight fractions, you'll have to figure in the density of each phase. Hint: Neither element is very soluble in the other except in the liquid state.
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