Romero was the author of the respected reference book Warman's Jewelry, which identifies and values 18th- through 20th-century jewelry. Her profound knowledge of the subject, combined with her personal passion for antique and collectible costume jewelry, made her a popular addition to the antiques lecture circuit. Romero traveled throughout the United States addressing students, collectors and fellow appraisers at institutions including Hofstra University, the Jewelry Design Department at the Fashion Institute of Design & Merchandising in Los Angeles, and the Northwest Gemological Institute in Bellevue, Washington. She also taught the Antique and Period Jewelry for the Gemology department at Santiago Canyon College in Orange County, Calif.

She attained a national profile as an appraiser for WGBH/PBS Television's Antiques Roadshow. In her on-camera appearances, Christie never failed to wear favorite pieces from her own jewelry collection - always with her own unique flair.

Romero was also an instructor of jewelry history for the National Association of Jewelry Appraisers (NAJA) and Revere Academy of Jewelry Arts. She held memberships in the professional organizations the American Society of Jewelry Historians, the Association for the Study of Jewelry and Related Arts (ASJRA), the Society of Jewellery Historians (U.K.), the NAJA, and the Costume Society of America.

The family has requested that in lieu of flowers donations can be made to the Pancreatic Cancer Action Network.