Paper can be made from a variety of materials, but perhaps one of the most unusual and environmentally friendly is paper made from stones.
Stone paper is known by many names including rock paper, limestone paper, eco-stone, and synthetic paper.
How it's made
Stone paper is made with a mixture of about 80% calcium carbonate which is also used in the manufacture of conventional tree-based paper. The calcium carbonate usually comes from limestone, marble and other stones collected as waste material from existing quarries for the building and construction industry. The stones are ground down to a fine chalk-like powder then a small quantity (about 20%) of non-toxic resin (HDPE- High Density Polyethylene) is added as a binder for the calcium carbonate. Together these materials create a soft, smooth, bright white paper that is tough, durable and both water and tear resistant. The paper is chlorine free, acid free, and safe for the environment.
The ECO benefit
• One ton of virgin paper uses 20 trees, 36,000 BTU’s of energy, creates 16,000 gallons of contaminated waste water, uses bleach, and contains 20-30% calcium carbonate (stone).
• One ton of recycled paper uses 4 trees, 22,000 BTU’s of energy, creates 9,000 gallons of contaminated waste water, uses bleach, and contains 20-30% calcium carbonate (stone).
• One ton of stone paper uses 0 trees, creates absolutely no waste water, and uses half the energy of virgin paper and 1/3 the energy of recycled paper. Stone paper does not require bleaching chemicals and generates no air pollution.
Stone-based paper is recyclable with both paper and plastic. Since it is stone it is not biodegradable. On exposure to UV light, e.g. from the sun, and moisture, the High Density Polyethylene breaks down after about a year returning the calcium carbonate to a power form. Egg shells are 95% calcium carbonate and decompose in a similar way. The HDPE is also recyclable and has the number "2" as its recycling symbol. Much of household waste is sent to WTE (Waste to Energy) plants where it is incinerated, scrubbed of carbon, and ‘recycled’ into energy. Even conventional paper waste ends up in WTE plants. If stone paper ends up at a WTE plant it actually is a great contributor since it burns more cleanly than many other materials and does not produce toxins.
The calcium carbonate itself is the most abundant natural mineral on earth making up 70% of all minerals on the planet. Mining and quarrying operations already existing in the world scrape away tons of calcium carbonate each year in an effort to get at the ‘more precious’ minerals. This excess material makes calcium carbonate a great ‘filler’ for papers, plastics, some food products and many household products.
Stone-based papers are:
• Water Proof
• Grease Proof
• Tear Resistant
• Weather Resistant
• An alternative to synthetic papers such as Yupo, Tyvek and polypropylene films
• A great grease barrier
• A great outdoors product (with the addition of UV blockers)
Some stone-based paper brands include: FiberStone® Natural Stone Paper, Terraskin, and Rockstock.