(chemistry, archaic) The act, process, or result (in the process of parting) of alloying a button of nearly pure gold with enough silver to reduce the fineness so as to allow acids to attack and remove all metals except the gold.
quaternion
quaternion
noun
(mathematics) A type of four-dimensional hypercomplex number consisting of a real part and three imaginary parts (real multiples of distinct, independent square roots of −1 denoted by i, j and k); commonly used in vector mathematics and as an alternative to matrix algebra in calculating the rotation of three-dimensional objects.
