Apparatus and method for formation evaluation

A down hole tool positionable in a well bore having a wall and penetrating a subterranean formation, the formation having a fluid therein, the down hole tool comprising:

• a housing enclosing at least one evaluation cavity;
• a fluid communication device extendable from the housing for sealing engagement with the wall of the well bore, the fluid communication device having at least one inlet communicating with the evaluation cavity for receiving the fluid from the formation and depositing such fluid into the evaluation cavity;
• and
• a viscometer comprising:
• a sensor unit comprising:
• at least two spatially disposed clamps;
• and
• a wire suspended in tension between the at least two clamps and positioned within the evaluation cavity such that the wire is available for interaction with the fluid;
• and
• at least one magnet emitting a magnetic field interacting with the wire.

A method for determining a viscosity of a fluid within a well bore penetrating a formation having the fluid therein, comprising the steps of:

• positioning a fluid communication device of the down hole tool in sealing engagement with a wall of the well bore;
• drawing fluid out of the formation and into an evaluation cavity within the down hole tool;
• and
• measuring the viscosity of the fluid within the evaluation cavity with a viscometer having a wire positioned within the evaluation cavity and suspended between two clamps.