RE: [Demo notebook] Reference notebook: corrections and recurring beginner questions · RWI-09200

Case 51 — Crystal reflections: why a dark patch is not a coating test · source wording exercise

Correction note for “Crystal reflections: why a dark patch is not a coating test”: retain the wording beginning “Compare multiple controlled angles and describe the visible observation without asserting…” in the record. If later material changes it, add the date, the changed wording and the source for that change; do not invent a completed correction here. Retain the source wording beside any paraphrase.