Political instability and government both affect the availability of gemstones. The ruby mines of Myanmar (Burma) were annexed by military government, blocking a very central source of rubies. Rubies of the Thai-Cambodian border were then able to produce enough material to replace the supply from Myanmar. When gemstone color was inferior, contemporary heat treatments improved clarity and depth of color. This enabled Cambodian and Thai ruby sales to dominate the market. The presence of Khmer Rouge, followers of the Communist party in Cambodia, interrupted production from that country for a period of time. Today many mines in Thailand are wholly exhausted.

Diamonds still win the popularity contest for a fashionable engagement ring. Diamonds are currently sought after in many color variations, both heat treated and natural. Celebrity jewelry choices are a case in point. Blue Tanzanite, discovered in 1967, is mined in Tanzania from only one locality. Because of source diminishment, the perceived value of the rare stone continues to increase. ‘Buy now or it will be too late’ has become an important marketing tool in these cases.

After the birth of Louis Joseph, Marie Antoinette’s son, a letter was delivered to the queen, written by Boehmer and Bassenge, the famed jewelers. The letter’s contents concerned a diamond necklace believed to have been purchased by the queen through the intermediary actions of cardinal de Rohan. Marie in truth felt only disdain for the cardinal, so the letter shocked her. the cardinal had flaunted libels about the queen during his time as the French ambassador to Vienna. The cardinal returned to Paris in 1777, and Marie Antoinette had snubbed him ever since.

The diamond necklace was originally commissioned by Louis XV for his mistress, the Comtesse du Barry. Marie had not shown any interest in the ostentatious piece, which consisted of large diamonds, arranged in elaborate festoons, pendants, and tassels. Marie had in fact rejected several offers from Boehmer and Bassenge to sell it to her.

The cardinal had been in a flustered frenzy to be in the queen’s good graces, and was tricked into buying the piece for Marie by Jeanne, the Comtesse de Lamotte – Valois, a swindler at odds with the queen. Jeanne was also Rohan’s mistress in 1783. Using forged documents from another lover, Lamotte – Valois persuaded the cardinal that she was a dear friend of Marie, and that Marie had commissioned her to obtain the necklace with the cardinal’s assistance.

The deceived Rohan met up with an impersonator of the queen who ordered him to buy the necklace to restore his special position. After the cardinal purchased the necklace, it ended up being disassembled by Jeanne’s husband so the diamonds could be sold to Grey and Jeffries, jewellers in London, and resold.

In the end, Rohan was acquitted, but he was stripped of titles and banished from court. The Lamottes were sentenced to life in prison and branded as thieves. Most of the blame fell on the queen herself, despite her lack of involvement in the situation, due to her public unpopularity. Marie Antoinette’s reputation never recovered after this incident, which was perhaps the intended result of the lies and thievery.