I do believe Victorian glass head pin cubes like this one are among the best examples of product design ever, and this one I found with one single black head pin among the grid of white ones, like a black sheep amid the flock! With two groups of larger veil pins, a box of mourning pins, and a second smaller pin rectangle with pretty blue sides--all found together, and all in very nice condition.
For reference, cube: 1 5/8" cubed. All pictured included, exactly as found.