Glacial imagery can be a powerful tool for breathing exercises and meditation, as it helps evoke a sense of calmness and tranquility. Here's a guided visualization using glacial imagery for a breathing and meditation practice focused on the cranium:

Find a comfortable and quiet place to sit or lie down. Close your eyes and take a few deep breaths to settle into a relaxed state.

Imagine yourself standing at the edge of a vast, pristine glacier. Feel the coolness of the air and the refreshing sensation it brings to your body.

As you take another deep breath, visualize that with each inhale, you are drawing in the pure, crisp air from the glacier. Picture it entering your nostrils and traveling up to your cranium, filling your head with revitalizing energy.

As you exhale, imagine releasing any tension or stress that you might be holding in your cranium. Visualize the breath carrying away any negative thoughts or worries, leaving you feeling lighter and more at ease.

Focus your attention on the glacial ice. Observe its glistening white surface, reflecting the sunlight and creating a calming ambiance. Imagine this radiant light gently enveloping your head, bringing clarity and mental clarity.

With each breath, allow the glacial light to penetrate deeper into your cranium, reaching every corner of your mind. Feel it melting away any mental blocks or fog, leaving you with a sense of spaciousness and clarity of thought.

As you continue breathing, visualize the glacial light gradually transforming into a soothing blue color. This serene blue light flows through your cranium, washing away any remaining tension or discomfort.

Take a moment to appreciate the stillness and serenity of the glacial environment. Allow yourself to be completely present in this moment, fully connected to the coolness and tranquility of the ice.

When you're ready to conclude the practice, take a few deep breaths, slowly bringing your awareness back to the present moment. Gently wiggle your fingers and toes, and open your eyes, feeling refreshed and rejuvenated.

Remember, this is just one way to incorporate glacial imagery into your breathing and meditation practice. Feel free to adapt and modify the visualization according to your preferences and what resonates with you personally.