Shankhalipi

From the longer Wikipedia page 
Shankhalipi (IAST: Śaṅkhalipi) or "shell-script" is a term used by scholars to describe presently undeciphered ornate spiral characters assumed to be Brahmi derivative that resemble conch shells (or shankhas) which can tentatively be assigned a new script family. They are found in inscriptions across various parts of India except the far south and date to between the 4th and 8th centuries CE. Both Shankhalipi and ornate Brahmi were stylised scripts used primarily for names and signatures.
Category:Undeciphered inscriptions