Which of the following is NOT a type of luminescence?

Luminescence refers to the emission of light by a substance that has absorbed light or other electromagnetic radiation. There are several well-defined types of luminescence based on the source of energy causing the light emission.

Bioluminescence is the production of light by living organisms, commonly found in species like fireflies and certain types of jellyfish. Photoluminescence occurs when a substance absorbs photons and re-emits them as light, which is typically observed in various materials used in lasers and fluorescent lights. Thermoluminescence is the process where a material emits light upon being heated, often used in dating archaeological finds or in certain types of glow-in-the-dark materials.

Metalluminescence, however, is not a commonly recognized type of luminescence in scientific literature. While various interactions concerning metals can produce light, the term "metalluminescence" lacks a clear definition and is not widely accepted or utilized in luminescence studies.

Thus, the correct answer identifies that metalluminescence is not an officially recognized type of luminescence, while the others are well-established categories in study and application.