Barium Sulfate (BaSO4) (98.5% Purity 0.7 micron CAS:7727-43-7)

NOT FOR HUMAN CONSUMPTION

Note: the loonie in the small photo is just for size reference (not included).

Barium sulfate is a remarkable substance that has many applications, including:

1. Heat-reflecting white paint. Barium sulfate is highly reflective of a broad spectrum of light, including visible light (such that it appears very white when used as a white pigment for paints), plus infrared and ultraviolet. Recently, researchers have successfully explored using it as an ingredient in paint that reflects greater than 98% of all solar radiation, thus cooling surfaces to which it has been applied (see also the YouTube video below).
2. Radiocontrast agent. Barium sulfate in suspension is often used medically as a radiocontrast agent for X-ray imaging and other diagnostic procedures.
   
3. Pyrotechnics (a niche use): barium compounds emit a characteristic green light at high temperatures.

We are presently offering 2 sizes: (1) a 0.6-gallon pail (~2.7 liters) that holds 2 kg of Barium Sulfate; or (2) a 500 ml bottle with a child-resistant lid that holds 375 grams of Barium Sulfate.

We are quite intrigued by its application as a heat-reflecting paint to save energy and cost, such as the following rather inspirational video:

For reference, if you'd like to make reflective paint using Barium Sulfate, we recommend starting with about 1.5 parts paint to 1 part Barium Sulfate, or 60% paint to 40% Barium Sulfate. More paint tends to yield better durability, whereas more Barium Sulfate yields better reflectivity. Here are a couple of sources for reference: Reflectance of Barium Sulfate and White Paint Mixtures (triticeaecap.org), and Ultrawhite BaSO4 Paints and Films for Remarkable Daytime Subambient Radiative Cooling | ACS Applied Materials & Interfaces.

For those interested, below are some detailed specs from our supplier: