Meaning
A diamond made of four curved petals around a small dot, a little like a flower or a cut gem, usually in blue. It is mainly a decorative symbol with a cute, ornamental feel.
People use it to decorate bios, section headings and usernames, or as a fancier bullet than 🔹: “💠 Menu 💠 Booking 💠 Contact” It can also suggest a crystal, a snowflake-like pattern or something precious. Its meaning stays loose, so the context does the talking.