Sodalite and lapis lazuli: blue stones that are often mixed up

Lapis lazuli is technically a rock rather than a single mineral, made mostly of lazurite along with calcite and, very often, visible flecks of pyrite scattered through it, which is one of the most useful identifying features since those metallic gold flecks are genuinely diagnostic. Sodalite is a single mineral, generally a more uniform blue without the pyrite flecking, and often shows white calcite veining rather than the golden pyrite lapis typically displays. Both sit in a similar hardness range, around 5 to 6, so hardness alone will not separate them, the presence or absence of pyrite flecks is the more reliable field clue.