Vivid red rubies, often referred to as "pigeon blood rubies," are highly prized for their intense, deep red color. This color is a result of the presence of chromium, which gives rubies their signature hue. The most valuable rubies exhibit a vibrant, almost glowing red that can sometimes appear to change in intensity depending on the light.

In terms of physical properties, rubies are a variety of corundum and rank 9 on the Mohs scale of hardness, making them one of the hardest gemstones. They are often cut in various shapes, with the most popular being oval or cushion cuts, which enhance their color and brilliance.

Metaphysically, rubies are associated with passion, love, and energy. They are believed to stimulate the heart chakra, promoting emotional healing and strengthening relationships. Rubies are also thought to bring vitality and motivation, encouraging a zest for life and enhancing overall well-being.

If you have any more questions or need further details, just let me know!