Newt's Tiffany Credit Sparks Influence Concerns No-interest credit extended as Callista Gingrich dealt with mining policy By Mary Papenfuss, Newser Staff Posted May 27, 2011 2:35 AM CDT 6 comments Comments Newt Gingrich and wife, Calista, wave at the audience gathered to hear him speak in Macon, Georgia. (Getty Images) (Newser) – At first, self-professed "frugal" Newt Gingrich's Tiffany bill of up to $500,000 just made him look ridiculously out of step with cash-strapped Americans. But now, the financial arrangement with the jewelry behemoth is raising questions about influence, notes Gawker. Gingrich and his wife enjoyed a special interest-free line of credit from Tiffany's while Callista Gingrich worked as chief clerk for the House Agriculture Committee. That's when Tiffany was lobbying the committee to influence silver mining policy, Spy Talk points out. Callista Gingrich listed debts to Tiffany of as much as $500,000 during two years at that time, notes the Washington Post. Interest on that bill for a typical consumer runs 21%, meaning the powerhouse couple ducked tens of thousands of dollars in interest fees. Spending by Tiffany's lobbyist, Cassidy & Co., zoomed while Callista worked for the committee. Now it looks like diamonds might not turn out to be a girl's—or a presidential candidate's—best friend.