We consider the Casimir Invariants related to some a special kind of Lie-algebra extensions, called universal extensions. We show that these invariants can be studied using the equivalence between the universal extensions and the commutative algebras and consider in detail the so called coextension structures, arising in the calculation of the Casimir functions.37K30, 37K05, 17B80 * On leave of absence from the Faculty

We consider a special kind of Lie-algebra extensions, called "universal" extensions, introduced recently. We investigate the quadratic Casimir invariants for the "universal" extensions, their reductions and extensions.