Choose a letter, pick a stone from the list, and read about it: what it is made of, how hard it is, what it looks like, what it has traditionally been said to do, and how to look after it.

450 minerals

Corundum

The Hard Gem of Many Colors

Also known as: Adamant, Hyacinthos, Asteria

Root chakra

About the stone

Corundum crystal — Photo: Ra'ike (see also Ra'ike on de.wikipedia, CC BY-SA 3.0, via Wikimedia Commons

Corundum is aluminum oxide, a mineral prized for its hardness and best known through its gem varieties: red ruby and sapphire in other colors, including pink-orange padparadscha. Known for thousands of years, it has no recorded single discoverer; John Woodward used the name “corinvindum” in 1725, derived from Sanskrit kuruvinda, and Richard Kirwan adopted the spelling “corundum” in 1794. Important sources include Myanmar, Sri Lanka, India, Madagascar, Mozambique, and Montana, USA. Historical names include adamant, hyacinthos, and asteria, though these older terms were not always exclusive to corundum. Its lore varies by gem variety: rubies symbolize vitality and protection, while sapphires represent wisdom, faithfulness, and heaven.

Mineral data

Chemical composition: Corundum is an aluminum oxide mineral, Al₂O₃. Its red variety is ruby, and every other color, including blue, is called sapphire.
Hardness: 9 on the Mohs scale.
Color: Every color, from colorless, gray and brown to pink, red (ruby), blue, yellow, green and orange (sapphire).

Metaphysical data

Corundum, recognized as one of the hardest natural minerals and the family of ruby and sapphire, has been utilized in metaphysical practices to build strength, resolve and lasting commitment.

Grounding and Stabilizing Energy

Corundum is believed to carry a durable, enduring energy that reflects its extraordinary hardness and resilience.
It is thought to strengthen resolve and perseverance, helping one hold to a commitment through challenges.

Emotional Healing

Its different colors are linked with different feelings, such as passion in red, calm in blue and cheer in yellow.
It is thought to support emotional stamina, helping one stay steady when situations test one's patience.

Harmonizing Energy Centers

Corundum varieties are linked with different chakras by their color, red with the root, blue with the throat or third eye, and yellow with the solar plexus.
Choose the color that matches the center you wish to work with in meditation.

Zodiac Associations

Corundum as a family is not strongly tied to one particular zodiac sign, although ruby and sapphire have their own traditional associations.
Because it comes in every color, many people pick the corundum that feels closest to their own sign or season.

Spiritual Growth

In meditation it is used to cultivate loyalty, devotion and a lasting sense of purpose.
It is treated as a symbol of clarity and strength of character, reminding us that pressure over time can create something brilliant.

Physical Healing

This information is for general interest and is not a substitute for professional medical advice, and the stone does not treat any condition.
In crystal lore it is simply valued as a stone of vitality and stamina, a durable companion during demanding times.

Care and handling

Corundum is extremely hard, 9 on the Mohs scale, and very durable, so it can be cleaned with mild soap, lukewarm water and a soft brush. Ultrasonic and steam cleaners are generally safe for clean stones without fractures or fillings. Avoid harsh chemicals on treated or fracture-filled stones. It is tough but can still chip along its edges, so store it apart from other gems.

Individual experiences with Corundum vary, and its effects are personal. Hold it mindfully, notice what its color brings to mind, and use it as a steady symbol of strength and commitment.