Re: Ionic silver with vitamin C?

Color is relative to particle size and density. Which you saw first hand when you added Vitamin-C to your solution. Which is rather interesting as your silver ppm would not change(that would be magic). - But the particle size and color changed accordingly.

Which raises some rather interesting questions with respect to your proposed statement. ie, if oxidation results in the dissociated of elemental silver(AKA silver ions), and reduction is the opposite effect, then how could we end-up with more particles than we started with?

Taking things a little further, I could see where the surface value could go up as a result of the increase in particle size, though it's very unlikely that we could ever end-up with an increase in particle count as a result of reduction as this implies simplification.

And to help illustrate my point, let's imagine for a moment that we started with an ionic solution weighing-in at 15ppm. Assuming, that we've confirmed this using an analytically scale, and know without a doubt that our solution contains no more than 15mg of silver. (less is possible, though more being impossible).
That being said our solution is clear at this point. Which is inherent of an ionic solutions as the particle size is most often too insignificant to disperse light at this concentration. Though it remains that we have a given particle count(in form of ions), in our solution.

But what happens when we add an additive such as Vitamin-C into the solution?

If we concede to the fact that the addition of the Vitamin-C results in a reduction(aka stabilization) of our ionic component, then the question arises as to whether or not we end-up with more or less particles than with what we started with? IOW. When these ionic particles bind with the reducing agent to form a larger molecule(aka Vitamin-C), do we end-up with a greater or lesser particle count? Or as you yourself put it, an increase in colloids?

col·loid:
a homogeneous, noncrystalline substance consisting of molecules or particles of one substance dispersed through a second substance. Colloids include gels, sols, and emulsions; the particles do not settle and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.

Something to think about.

PS. I myself don't like what many internet sellers do to the Colloidal Silver knowledge base as they often confuse people by either; making-up stuff or distorting facts so as to help promote or sell their products. One such motion took place when the infamous line of True Colloidal Silver came into light. - see: Oh that isn't what we'd call a true colloidal silver... but this one is right here. :)