Well, macro is a little out of my area, but here goes anyway. This is called "salmiakki" in Finnish, or salty liquorice. It's basically liquorice flavoured with ammonium chloride, and it's used in Finnish candy quite often. People outside the Nordic countries don't usually like it. It's very salty, but once you grow to like it, there's no going back. In the photo is Apothecary's Salmiac, and it's diameter is around 7 millimeters. It's black, so the only B&W conversion here is removing the blue sky around it. It's lying on a mirror (hence the sky), and you can see the bottom, too. This is a stacked photo with 5 exposures, taken with a vintage 60's Nikkor 24mm with an extension tube.
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