The Hach lab handbook says that, depending on concentration and particle size, that some light will be absorbed, some will be reflected, some will be refracted, and some will be absorbed and re-emitted at a different wavelength and at a different angle from the incident light.
JOH -----Original Message----- From: Frank Key [mailto:[email protected]] Sent: Tuesday, March 27, 2001 11:01 AM To: [email protected] Subject: Re: CS>Tyndall yet clear Marshall wrote: > You misread what I said. I said that absorption without any scattering will be clear, but likely colored, and that scattering without absorption will be milky, but > with little if any color except for possibly tyndall blue. > > The examples you give below have both tyndall and scattering, the milky part is from scattering, not absorption. High ppm CS will have both and have both > characteristics. Actually, colloidal silver particles both scatter and absorb light. To prevent absorption, the particle would have be a perfect reflector, like a mirror surface, which it is not. So, some amount of energy is absorbed and some is reflected. That energy which is reflected constitutes the scattered portion of light. (This is the light that a PCS uses to determine the size of the particles.) However, if all the energy was absorbed with out scattering, the appearance of color would be determined by the complement of the visible light that was absorbed. So, if the particles were 30 nm and completely absorbed the light, there would still be no color, since there is no complement in the visible spectrum. On the other hand, I do not believe that particles actually exist that would only absorb and have no reflection, so the point is moot. In any case, I think is safe to pronounce this horse dead. frank key -- The silver-list is a moderated forum for discussion of colloidal silver. To join or quit silver-list or silver-digest send an e-mail message to: [email protected] -or- [email protected] with the word subscribe or unsubscribe in the SUBJECT line. To post, address your message to: [email protected] Silver-list archive: http://escribe.com/health/thesilverlist/index.html List maintainer: Mike Devour <[email protected]>
