Most stories will have similar weapons, aliens, space travel etc, but in The Edge Chronicles there is a substance called phraxdust that can purify water when mixed with contaminated liquids. I have not read or seen something similar to this used outside of the series and wondered if it was inspired form an old legend or something I have just never heard of. The series was started in 1998.

So, does anyone know of something like this?


Phraxdust was a substance created when Stormphrax crystals were ground in true twilight. A fine sepia powder that seemed to flow like liquid, Phraxdust was capable of purifying the foulest of water, and was therefore highly valued and prized. REF: Edge Chronicle Wiki - Phraxdust

The closest thing I can think of in real life would be a substance like Activated Carbon/charcoal in a process called adsorption.

  • Activated charcoal is used in water filters, medicines that selectively remove toxins, and chemical purification processes. Activated charcoal is carbon that has been treated with oxygen. The treatment results in a highly porous charcoal.

enter image description here

  • These tiny holes give the charcoal a surface area of 300-2,000 m2/g, allowing liquids or gases to pass through the charcoal and interact with the exposed carbon.

  • The carbon adsorbs a wide range of impurities and contaminants, including chlorine, odors, and pigments. Other substances, like sodium, fluoride, and nitrates, are not as attracted to the carbon and are not filtered out.

  • Because adsorption works by chemically binding the impurities to the carbon, the active sites in the charcoal eventually become filled. Activated charcoal filters become less effective with use and have to be recharged or replaced.

  • If I could get some charcoal like this, I'm half tempted to try. – Brandon Aug 1 '13 at 20:02
  • 1
    It is a common element in filtration technologies and you can buy it online to experiment with. – Thaddeus Howze Aug 1 '13 at 20:10

Water purification tablets contain an iodine compound that can be used to disinfect water of common bacteria, although they wont filter out contaminants such as silt and other grit, nor will they affect poisonous compounds.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.