The combination of Pietersite, Black Obsidian, and Hematite is believed to create a powerful triad of spiritual awakening, protection, and grounding. Each stone contributes its own unique energetic properties, resulting in a synergistic effect. 
Here's a breakdown of the individual and combined meanings:
Individual Meanings:
Pietersite:
Known as the "Tempest Stone", it is associated with transformation, courage, and change.
It is believed to stimulate the third eye and crown chakras, enhancing intuition, spiritual insight, and psychic abilities.
It can help access and release buried emotions, promoting emotional healing and growth.
It is said to aid in navigating life transitions with greater confidence and self-awareness.
Black Obsidian:
A powerful grounding and protective stone that forms a shield against negativity and psychic attacks.
It is believed to cut through illusions and reveal the truth, promoting clarity and inner wisdom.
It can assist in releasing emotional baggage and breaking unhealthy attachments.
It is associated with shadow work, helping to bring awareness to repressed aspects of the self for healing.
Hematite:
A grounding stone that connects you to the earth, promoting stability and security.
It absorbs negative energy and helps transmute it into positive energy, protecting the aura.
It enhances concentration, focus, and memory.
It is believed to encourage balance, strength, and vitality. 
Combined Meaning:
Together, these stones are thought to offer a potent combination of energies:
Spiritual Transformation and Protection: Pietersite fosters spiritual growth and intuition while Black Obsidian provides strong protection against negative energies and psychic attacks.
Grounding and Clarity: Hematite anchors you to the present moment and promotes stability, while Black Obsidian clears away illusions and reveals the truth.
Emotional Healing and Empowerment: Pietersite helps release suppressed emotions, Black Obsidian supports emotional processing, and Hematite fosters a sense of strength and balance. 
In essence, this combination is thought to provide a powerful support system for personal growth, spiritual awakening, and navigating challenging times with courage, clarity, and strength.