Vintage Pyrex measuring cups are crafted from borosilicate glass, known for its thermal resistance and clarity. This type of glass ensures that the measuring cups can handle extreme temperature changes, making them suitable for both hot and cold liquids. The iconic designs often feature clear volume markings, allowing for precise measurements. Notably, many vintage Pyrex measuring cups come in a variety of colors, including the famous Fire King red, turquoise, and amethyst, which add vibrant touches to any kitchen collection.