The Collaborative International Dictionary of English v.0.48:

Valuation \Val`u*a"tion\, n.
   1. The act of valuing, or of estimating value or worth; the
      act of setting a price; estimation; appraisement; as, a
      valuation of lands for the purpose of taxation.
      [1913 Webster]

   2. Value set upon a thing; estimated value or worth; as, the
      goods sold for more than their valuation.
      [1913 Webster]

            Since of your lives you set
            So slight a valuation.                --Shak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

valuation
    n 1: an appraisal of the value of something; "he set a high
         valuation on friendship" [syn: evaluation, valuation,
         rating]
    2: assessed price; "the valuation of this property is much too
       high"

Bouvier's Law Dictionary, Revised 6th Ed (1856):

VALUATION. The act of ascertaining the worth of a thing; or it is the
estimated worth of a thing.
     2. It differs from price, which does not always afford a true criterion
of value, for a thing may be bought very dear or very cheap. In some
contracts, as in the case of bailments or insurances, the thing bailed or
insured is sometimes valued at the time of making the contract, so that if
lost, no dispute may arise as to the amount of the loss. 2 Marsh. Ins. 620;
1 Caines, 80; 2 Caines 30; Story, Bailm. Sec. 253, 4; Park Ins. 98; Wesk.
Ins. h.t.; Stev. on Av. part 2; Ben. on Ins. ch. 4.