It works!

This is by far the most complicated alchemical machine I've ever attempted. When I first saw the puzzle, I thought just pull two inputs, do a bunch of checks for duplicates with the purification glyph and use input suppression to mix quicksilvers and lead for the counter. Not too bad! I threw together a solution ready to claim my victory. A bit complicated, but a good nights work had my machine completed.

But when I submitted I saw the fatal flaw in my approach - pairs of Gold fail the purification check. Worse, upon rereading the notes, I then saw input batching was not permitted! All the conditional tests I could think of required modification or destruction of the input, there was no choice but to somehow duplicate the input. But I couldn't work my head around how to make copies nor how many copies would I need.

I kept coming back to my original solution, could I somehow just handle the dual gold edge case? Then inspiration - if Gold doesn't purify it also doesn't project - we can test for it using quicksilver! Further, I can count how many projections to get to Gold from one element of the input and spin the Metal-Berlos to extract the right element. In one stroke, I knew how to solve both the duplication and the dual-Gold edge case. Three copies would do, two as before and one to search for gold.

For a game which gives you infinite space I always seem to end up very cramped. If I had realised earlier that duplication was the slowest stage of my solution (and by a long way), I probably would have spaced things out differently. I thought about trying to better dispose of the waste but just gave up, turned out that I needed the disposal glyph in the middle of the duplication pipeline and trying to thread all my other waste through there just felt like an extra unnecessary headache, so waste sticks it is. Actually judging from the metric probably only the metal-berlo waste really needs to be managed properly, the rest of the waste stations are probably pretty close to cost neutral whether you go with sticks or disposal.

Honestly, this is the first time I wasn't sure I'd be able to complete the puzzle at all. Very happy to get it up and running!