CZ stones, or cubic zirconia stones, are man-made gemstones that are designed to look like diamonds. They are made of zirconium dioxide (ZrO2), which gives them a cubic crystalline form and a high level of brilliance. CZ stones are classified as diamond simulants, which means they are stones that look similar to natural diamonds but are made of different materials. They are colorless and can be cut into many common diamond shapes, such as round, princess, pear, and cushion. CZ stones are affordable and unique alternatives to fancy colored diamonds or colored gemstones like emerald, ruby, and sapphire. They can also be color-treated with different elements, resulting in a rainbow of hues. CZ stones are popular in fashion and costume jewelry because they are attractive yet affordable. They are also used in engagement rings, where they offer customers more control over the shape, style, and cost of their ring. CZ stones are not as hard as diamonds, which means they can scratch more easily. They are also not as heat-resistant as diamonds, which means they can crack or burn if exposed to high temperatures.