A cross intended for the altar or a procession is worked by a metalsmith, not whittled by hand, and its material is chosen deliberately.
What it is made from
Most altar and processional crosses are cast or wrought in brass, bronze or silver, often gilt, and mounted so they can stand upright or be carried on a pole at the head of a procession. Personal crosses run from a plain wooden pendant on a cord, cut from olive wood or pine and sometimes inlaid with mother of pearl in the workshops that have supplied Bethlehem pilgrims for generations, to a bishop's pectoral cross in gold set with stone. Stone crosses are a separate craft entirely: the standing crosses of early medieval Ireland and Britain were carved from single blocks of granite, covered edge to edge in relief panels, a monumental form with no small counterpart.
Who blesses it, and what happens when it breaks
A priest blesses a cross intended for devotional use, after which Catholic and Orthodox custom treats it as a sacramental rather than an ornament. A blessed cross that is broken or worn through is not thrown out with ordinary refuse, it is burned or buried, or handed to a priest or sacristan for that disposal, the same treatment given to worn vestments and last year's palm branches. The form itself has travelled: the plain Latin cross of the West, the eight pointed Coptic cross, the ringed Celtic cross, and the ornate silver processional crosses of Ethiopia, worked by hereditary smiths in patterns particular to each region, are one object continually reshaped by whoever is carrying it.