I recently bought a vintage chanel on eBay, the serial number begins with a 3xxxxxx.. The card has a light blue dot on the upper right hand corner with CC circled in white on the inside of the dot. Also the gold trip on the card gives off rainbow color in the light? Can this be fake or just a variation due to older style? I thought I read some where that authenticity cards cann't give off color. I ouwld post pics but I dont have my cam.