The National Archives now houses the Declaration of Independence, the Constitution, and the Bill of Rights. None of the three are written on hemp paper, but on parchment. Parchment is made from processed animal skin, most often sheepskin. Iron gall ink was used to write the Declaration of Independence. This type of ink was made with water and ground-up insects such as beetles or worms. Hemp has been used for clothing, food, building materials, and paper since ancient times. After the Industrial Revolution, interest in hemp waned due to changes in agriculture and forestry practices. Since then, research has shown that hemp is a versatile crop that can be used in many ways beyond its traditional applications. Today, there are several types of papers used by printers. The choice of paper affects the look and feel of the printed document, as well as how it performs. For example, printer's ink is not waterproof, so if you print on normal copy paper, it will need to be laminated or coated to prevent leaking or smudging. Hemp paper has many advantages over traditional paper. It is 100% natural, renewable, biodegradable, and free of toxic chemicals. There are two main varieties of hemp: industrial hemp and marijuana hemp. Industrial hemp contains less than 0.3% THC (the psychoactive ingredient in marijuana), while marijuana hemp contains up to 3%.