Given a positive integer
n≥2, an arbitrary field
K and an
n-block
q=[
q(1)|…|
q(n)] of
n×
n square matrices
q(1),…,
q(n) with coefficients in
K satisfying certain conditions, we define a multiplication ·
q :
Mn(
K)$¥otimes$
K Mn(
K)→
Mn(
K) on the
K-module
Mn(
K) of all square
n×
n matrices with coefficients in
K in such a way that ·
q defines a
K-algebra structure on
Mn(
K). We denote it by
Mqn(
K), and we call it a minor
q-degeneration of the full matrix
K-algebra
Mn(
K). The class of minor degenerations of the algebra
Mn(
K) and their modules are investigated in the paper by means of the properties of
q and by applying quivers with relations. The Gabriel quiver of
Mqn(
K) is described and conditions for
q to be
Mqn(
K) a Frobenius algebra are given. In case
K is an infinite field, for each
n≥4 a one-parameter
K-algebraic family {
Cμ}
μ∈K* of basic pairwise non-isomorphic Frobenius
K-algebras of the form
Cμ=
Mqμn(
K) is constructed. We also show that if
Aq=
Mqn(
K) is a Frobenius algebra such that
J(
Aq)
3=0, then
Aq is representation-finite if and only if
n=3, and
Aq is tame representation-infinite if and only if
n=4.
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