- Product: Natural Citrine
- Form: Oval
- Color: Yellow Brown
- Size: 15.80 x 11.90 x 16.00 x 12.00 mm
- Weight: 8.25–8.65 carats
- Clarity: No visible inclusions
- Treatment: heat-treated
- Origin: Brazil
Citrine is a variety of quartz whose colour ranges from pale yellow to brown due to a submicroscopic distribution of colloidal ferric hydroxide impurities. Natural citrines are rare; most commercial citrines are heat-treated amethysts or fumed quartz. However, a heat-treated amethyst will have small lines in the crystal, as opposed to the cloudy or smoky appearance of a natural citrine. It is almost impossible to visually differentiate between cut citrine and yellow topaz, but they differ in hardness. Brazil is the world's largest producer of citrine, with much of its production coming from the state of Rio Grande do Sul. The name is derived from the Latin word citrina, which means 'yellow' and is also the origin of the word 'lemon'. Sometimes citrine and amethyst can be found together in the same crystal, which is then called amethyst. Citrine has been called the "merchant's stone" or "money stone" because of the superstition that it will bring prosperity. Citrine was first valued as a gemstone in Greece between 300 and 150 BC, during the Hellenistic era.