Pigeon's blood is one of the oldest and most exacting colour appellations in the ruby trade. It describes a pure, highly saturated red — vivid rather than dark, with a faint purplish cast rather than an orange one — and, in many stones, a lively internal glow created by the red fluorescence natural to chromium-bearing corundum. The term is a description of colour quality, not of origin or species.
Every stone gathered on this page is a Mozambique Ruby. Mozambique has become one of the principal modern sources of fine red ruby, and material from the region is well known for reaching the depth of red the trade associates with this description. Because all stones here share one variety, your comparison is essentially one of individual character rather than of species.
When choosing, weigh saturation against tone: the finest reds hold their colour without sliding into darkness under low light. Consider how the cut returns light across the table, how evenly colour is distributed, and how the stone behaves in daylight versus lamplight. Clarity in ruby is judged with realistic expectations — inclusions are common and, when well placed, need not diminish beauty.