Colloids
A colloid consists of small particles of one substance suspended in another, first described by Thomas Graham in the late nineteenth century, for example see Ref. 1.
Interesting reading
- Wilson Poon, Peter Pusey and Henk Lekkerkerker "Colloids in suspense", Physics World April pp. 27-34 (1996)
- Alfons van Blaaderen "Colloids get complex", Nature 439 pp. 545-546 (2006)