Discuss PGroot's answer to: What is the density of dry ferric sulfate?

Alas, Wikipedia.  If their values and ethics assessments are any indication of their thoroughness, then I have to question the rest of their work.  I have found so many errors on that site that I only rarely use it.  It is handy for material that is NOT subject to interpretation.  However even some of their scientific articles are fraught with error.

I looked up the Product Reference Sheet from one of the major suppliers of Ferric Sulfate that I have in my library: Morton Chemicals Ltd, Nanaimo BC.  Usually they deal in quantities that travel best by railcar or bulk ship.  I doubt that they have changed much in their preparation methods since 1992. 

It is good that you consult though.  I'll give you that.

Here's a Material Safety Data Sheet which gives specific gravity 3.097

http://www.sciencelab.com/msds.php?msdsId=9924046