Costume jewelry is jewelry that is made of less valuable materials including base metals, glass, plastic, and synthetic stones, in place of more valuable materials such as precious metals and gems. Costume jewelry is usually inexpensive, and often flashy. Its main use is in fashion, as opposed to real (fine) jewelry, which regarded primarily as collectibles, keepsakes, or investments. Originally, costume or fashion jewelry was made of inexpensive simulated gemstones, such as rhinestones or Lucite, set in pewter, silver, nickel or brass. Modern costume jewelry incorporates a wide range of materials. High-end crystals and cubic zirconia simulated diamonds, and some semi-precious stones used in place of precious stones. Metals include gold- or silver-plated brass, and sometimes vermeil or sterling silver. Lower-priced jewelry may still use gold plating over pewter, nickel or other metals; items made in countries outside the United States may contain lead. Some pieces incorporate plastic, acrylic, leather, or wood.