Stone

As a symbol, stone represents stability, durability, reliability, immortality; sure foundations; the eternal; static life.
Tall up-right stones represent supreme support of all things in the Universe.

Permanence and Eternity:

Endurance - Stone represents what lasts, what withstands time and weathering
Immortality - Unlike organic materials, stone seems almost eternal
Memory and monuments - Gravestones, memorials, and ancient structures preserve memory across generations

Strength and Stability:

Foundation - The "cornerstone" or "bedrock" upon which things are built
Reliability - "Solid as a rock" suggests dependability and steadfastness
Protection - Stone walls and fortresses symbolize security and defense

Spiritual and Sacred:

Divine presence - Sacred stones, altars, and stone temples mark holy places
Transformation - The philosopher's stone in alchemy represents ultimate spiritual transformation
Covenant - Stone tablets (like the Ten Commandments) represent divine law and sacred agreements

Hardness and Coldness:

Emotional barriers - A "heart of stone" suggests callousness or inability to feel
Stubbornness - Being "stone-faced" or immovable
Death - The coldness and stillness of stone can represent lifelessness

Hidden Potential:

Precious gems - Rough stones contain hidden beauty waiting to be revealed
Raw material - Stones that can be carved, shaped, or polished represent latent possibility

Biblical and Religious:

Christ as cornerstone - Foundation of faith
Peter (meaning "rock") - Steadfast foundation of the church
Stumbling block - Obstacle in one's path