reflective sand banner.jpg

Composition & Characteristics

Our reflective sand is actually just hollow silica microspheres, essentially very small spheres that float when put in water or melt ponds. Microspheres are used in composite materials, medical technology, biotech, paints and coatings, cosmetics and personal care, automotive, aerospace, and others. They are even applied by the pharmaceutical industry to encapsulate drugs for targeted delivery. Hollow microspheres are typically used as additives to composite materials to lower their density, and have been used and deployed in the environment for decades--they may even be in your drywall.

Here are some of the characteristics that make reflective silica microspheres a great candidate for ice preservation:

  • Low density
  • Low weight
  • Low thermal conductivity
  • Low water absorption

  • Inert (chemically unreactive)
  • Oleophobic (will not attract oil-based pollutants)
  • Consistent distribution
  • Free flowing


Read about how silica microspheres are safe for life and ecosystems on our Material Safety page.

Cost & Scalability

Mimicking the reflective properties of bright multiyear ice is one of the most inexpensive proposals for slowing climate change, at at least 1/10th of the cost of other solutions. Unlike those solutions that must go through another decade of testing, Ice911 has already spent a decade testing its reflective sand. Through years of careful experimentation, we have isolated the most effective and safe material way to increase the reflectivity of ice. In addition, our reflective sand is producible today at the quantities needed to make a significant impact on global temperatures. With the right funding and permits, we can responsibly scale up to begin preserving the Arctic ice cap.


Because our goal within a few years is to protect 15,000 to 100,000 square kilometers of ice, Ice911 has pioneered several methods for spreading the sand without putting humans on sea ice. In April 2017, we successfully tested our first automated deployment and covered approximately 17,500 square meters of Arctic ice. In 2018, we covered 15,000 square meters of ice with the same automated method. At scale, we would employ a VLCC ship. See more on our At Scale page.

Production Process

Silica microspheres are typically produced by a process in which a raw material feed (silica sand) is introduced at the top of a heating chamber by a vibratory funnel. The particles are then transported to a flame by a carrier gas (which further disperses the particles) The particles fall through the flame front where fusion occurs. As they fall, they cool and separate from the gas mixture by a cyclone. In the case of the microspheres employed by Ice911, the raw material is soda-lime glass.