Growing — Crystal

Once a stable nucleus exists, growth proceeds as additional molecules diffuse through the medium and attach themselves to the crystal's surface. Attachment happens most readily at defects, corners, and steps—locations where incoming molecules find more adjacent bonding partners. This preferential attachment explains why crystals develop flat faces and sharp edges; molecules fill in reentrant corners faster than they build up perfect flat surfaces.

offers a slower alternative. A dilute solution left open to air gradually loses water, increasing concentration until crystals form. This method produces smaller but often more perfect crystals, as growth proceeds under near-equilibrium conditions. Epsom salt (magnesium sulfate) grown by evaporation produces delicate needle-like crystals overnight. crystal growing

Not all solids are crystalline. Glass, plastics, and many gels are amorphous—their atoms lack long-range order. The distinction matters: crystalline materials typically have sharp melting points, directional strength, and predictable electrical properties that amorphous solids lack. Crystal growth occurs through a process called nucleation and propagation. First, a tiny cluster of molecules—the nucleus—must form spontaneously in a supersaturated solution, melt, or vapor. This nucleation requires overcoming an energy barrier: smaller clusters tend to dissolve back into the surrounding medium, while clusters above a critical size become stable and begin growing. Once a stable nucleus exists, growth proceeds as