The smith forged caveja beating hot iron. To obtain a caveja with musical rings it was necessary to have a steel that solders easily, that doesn't fuse, doesn't crack under the strokes of hammer and that withstands an high temperature manteining its hardness.
Caveja had the duty to block the yoke, led by two cows, at the helm of wagons, plows, harrows, with braking function (avoided skidding forward of the helm); "caviotto" had the duty to block the yoke and the helm of towing (avoided skidding backwords of the helm).
It also had a simbolic and ritual function. By tradition, with caveja could predict the sex of unborn baby, calm the storms, defend the newlyweds, fight the spells.