The coin's core carries an image of a fetus, a universal symbol of human life, at the centre of both the millennium that ends and the new millennium that begins, which is symbolized by a sequence of rays within the coin's ring. The year 2000 is placed centrally at the lower part of the coin ring. On the right side of a brass ring is placed signature of the engraver (DM).

A fetus is a stage in the prenatal development of viviparous organisms. In human development, a fetus or foetus is a prenatal human between the embryonic state and birth. The fetal stage of human development tends to be taken as beginning at the gestational age of eleven weeks, i.e. nine weeks after fertilization. In biological terms, however, prenatal development is a continuum, with no clear defining feature distinguishing an embryo from a fetus. A fetus is also characterized by the presence of all the major body organs, though they will not yet be fully developed and functional and some not yet situated in their final anatomical location.

The central part of the coin's core carries the designation of the nominal value 25. Within the numeral outlines, the figure of a pine marten running towards the right is shown; the marten's body is integrated with the numeral denoting the nominal value. In the bottom, central part of the coin's ring the coat of arms of the Republic of Croatia is impressed. A blooming laurel branch is placed in a semicircle on the left to the coat of arms, while a common oak branch with fruits is on the right. The top part of the ring carries the semicircular inscription The Republic of Croatia.

The word "kuna" means "marten" in Croatian since it is based on the use of marten pelts as units of value in medieval trading.

The martens are slender, agile animals, adapted to living in taigas, and are found in coniferous and northern deciduous forests across the Northern Hemisphere. They have bushy tails, and large paws with partially retractible claws. The fur varies from yellowish to dark brown, depending on the species, and, in many cases, is valued by fur trappers.

The coat of arms of the Republic of Croatia consists of one main shield and five smaller shields which form a crown over the main shield. The main coat of arms is a checkerboard (chequy) that consists of 13 red and 12 silver (white) fields. It's also informally known in Croatian as šahovnica ("chessboard", from šah, "chess"). The five smaller shields represent five different historical regions within Croatia.