There are worse places for a Mexican family to hock its jewels than the national pawnshop, headquartered atop the ruins of the Aztec emperor Montezuma’s residence in the heart of the capital.

The pawn palace, built of volcanic stone and eccentrically renovated over the past five centuries, once served as the treasure house for conquistador Hernando Cortés. Today it is where Mexicans trade in their wedding rings to pay for their children’s school uniforms.

Ordinary desperation brought Evelia Medina to the Nacional Monte de Piedad, literally the National Mountain of Pity. What she needed was some quick cash. In her hand were two slim gold chains and a ruby teardrop ring. Due last week: her telephone bill.

“I would prefer not to give my jewelry away, but what is the alternative?” Medina said. The 43-year-old mother of three, who works as a secretary to a notary, was counting on a $150 loan, which she planned to repay by March. Or maybe April.

“Toys,” she said. “They cost a lot.” A Christmas shopping spree had killed her budget and brought her to the end of a long line to wait for an appraiser to tell her what her trove was worth.

The National Mountain of Pity is the cash shack of first and last resort for millions of Mexicans — an estimated one in four families gets a micro loan — and the business of bailing citizens out of their financial jams is booming.

“I would call this unprecedented growth,” said Gustavo Méndez Tapia, spokesman for the enterprise, which many Mexicans call simply “the Mountain,” or sometimes “Aunt Pity.”

In 1990, the pawnshop had a few dozen branch offices scattered across the country. Now it has 169 outlets, and by year’s end there will be 272.

Mexico’s economy shrank about 7 percent in 2009, victim of the triple whammy of a swine flu epidemic, falling oil prices and global recession, marked by the sluggish spending of the country’s top trading partner, the United States. In January, Mexico’s annual inflation rate rose to 4.17 percent. The Central Bank reports that remittances from Mexican workers abroad, mostly in the United States, plunged almost 16 percent in 2009 compared with 2008, a record freefall for Mexico’s second-biggest source of foreign capital, after oil.

Meanwhile, consumers’ purchasing power has fallen by 41 percent during President Felipe Calderón’s tenure, even as a slight uptick in the minimum wage (to about $4.60 a day) was overwhelmed by higher transportation fares and prices for gasoline, electricity and food.

“It is hard times,” said Guadalupe Jiménez, 33, a store clerk with medical bills to pay, who came to the Mountain to trade a gold watch for a few hundred dollars, at an interest rate of 4 percent a month, for a term of no longer than 17 months. Jiménez said she comes two or three times a year. “But I have always paid the money back,” she said, proud that she, like 96 percent of the borrowers, reclaims her goods by repaying her loans.

The Mountain shelled out $1.4 billion in mini-loans last year, with the average value of each cash advance about $160. The pawnshop’s busiest months are January (when Christmas bills come due), March (Easter week holidays) and August (tuition fees, books, clothes for school).

Holy S&^% now that is a pawn shop!