Diamonds Are For Virgins?

This story in The Atlantic has given me pause:

A now-obsolete law called the "Breach of Promise to Marry" once allowed women to sue men for breaking off an engagement. Back then, there was a high premium on women being virgins when they married -- or at least when they got engaged. Surveys from the 1940s show that roughly half of engaged couples reported being intimate before the big day. If the groom-to-be walked out after he and the bride-to-be had sex, that left her in a precarious position. From a social angle, she had been permanently "damaged." From an economic angle, she had lost her market value. So Breach of Promise to Marry was born.

But in the 1930s, states began striking down the "Breach of Promise to Marry" law. By 1945, 16 states representing nearly half of the nation's population had made Breach of Promise a historical relic. At the same time, the diamond engagement ring began its transformation from decorative to de rigueur. Legal scholar Margaret Brinig doesn't think that's a coincidence, and she has the math to prove it. Regressing the percent of people living in states without Breach of Promise against a handful of other variables -- including advertising, per capita income and the price of diamonds -- Brinig found that this legal change was actually the most significant factor in the rise of the diamond engagement ring. 

So did good religious folk start using engagment rings much later? (Leaving aside my assumption that religious people are less likely to have "eaten Matzah on the eve of Pesach")

This also has ramifications for a question that does occaisonly come up:

So, should a jilted bride give back the engagement ring? Today, the answer is often yes. But back when rings first came into vogue, part of the point was that she wouldn't. It was a security against a default on the engagement