I don’t know what to call this pattern, but I like it!
Image 1: “The Maze” by Debralee Wiseberg (link and another gallery)… I think it’s corroded metal?
Image 2: 2,2-(Bipyridine)(Naphthalene)-fusion melt (25x)
Herb Comess. Honorable Mention, 1994 Nikon Small World Photomicrography Competition (link)