EN
A normal Banach quasi *-algebra (𝔛,) has a distinguished Banach *-algebra $𝔛_{b}$ consisting of bounded elements of 𝔛. The latter *-algebra is shown to coincide with the set of elements of 𝔛 having finite spectral radius. If the family 𝓟(𝔛) of bounded invariant positive sesquilinear forms on 𝔛 contains sufficiently many elements then the Banach *-algebra of bounded elements can be characterized via a C*-seminorm defined by the elements of 𝓟(𝔛).