VINTAGE Agate 12K Gold Necklace

This is a vintage Agate necklace is marked 1/20 12K GF (gold filled) LANG on the clasp. Age is unknown and the brand is LANG, possibly meaning the brand is from jewelry creator Jarmilla Lang, a brand est. in 1969---> I will not guarantee the brand but this is what my research turned up. This piece has been in storage for 2+ years in a smoke and pet free home. ABSOLUTELY NO TRANSACTIONS OFF POSHMARK! COMMENTS FOR OFF APP TRANSACTIONS WILL BE REPORTED & BLOCKED! Measurements (approximate): 20" chain, 10" chain "drop" when worn, total length when worn is 11.25" . When shipped, the necklace will be in a random jewelry box that I have so please do not equate any brand names on the box to the brand of the necklace or jewelry. . Age side note: I acquired it after my mom passed in '20, and I believe she acquired it after her mother passed in '14, but again I do not know the exact age. It's been in storage for 2 years in a smoke & pet free home.