The Blackwing Volume 55 features a design inspired by the Fibonacci sequence, a series of numbers that approximate the Golden Ratio.
Each pencil features a two-toned finish with a silver imprint, silver ferrule, pink eraser, and a balanced graphite. The width of each colour block is the sum of the widths of the previous two colour blocks (1, 1, 2, 3, 5, 8, 13, 21, 34, & 55mm). A simple formula with a magnificent result.