Final answer:
The image indicating a mineral breaking in a flat, even plane suggests it has cleavage, which is a break along weak chemical bond planes and is a key characteristic in mineral identification.
Step-by-step explanation:
The broken piece of mica you mentioned demonstrates what is known as cleavage, where a mineral breaks along planes where the chemical bonds are weakest, resulting in flat, smooth surfaces. Cleavage can be a useful property for identifying minerals because these planes reflect light when shone upon, appearing brilliant. Mica typically has a very thin, layered structure with a satin sheen and can peel off in thin sheets, which is indicative of its excellent cleavage along one plane. To accurately determine if cleavage is present on a mineral surface, one should use a hand lens to inspect for slight variations in elevation that indicate the presence of cleavage planes, as well as test for angles between these planes.