crystalline

Like a crystal. It implies a uniform structure of molecules in all dimensions. For example, phase change technology, widely used for rewritable optical discs, uses crystalline spots (bits) to reflect the laser beam. Amorphous, non-crystalline bits do not reflect light. See amorphous, nematic, phase change disk and phase change memory.

Crystalline Vs. Amorphous

This magnified UDO disk from Plasmon shows non-reflective amorphous (grey) and reflective crystalline (light/dark) bits. The crystalline area is not a single crystal, but a multi-crystalline region. Due to different crystal alignments and interaction of the beam used to image the material, the reflective bits appear variously light and dark. The different sizes of bits are due to UDO's encoding method. (Image courtesy of Plasmon, www.plasmon.com)