Contrary to popular belief, this item does not degrade while using non-combat magic.
The normal version requires 78 Attack and lasts for an hour of combat. After the time is up, the spear will vanish, although it can be alchemised before it turns to dust. If a player is made to lose a degrading Vesta's Spear in the Wilderness or inside the dangerous portal at clan wars, 780,000 coins will be dropped in its place.
A corrupt version also exists, which requires only 20 Attack and lasts only for 15 minutes of wielding (degrades even while not in combat).
As an hour contains 6000 ticks and the spear hits once per 5 ticks, you are able to hit 1200 hits with this spear before it degrades. Thus, each hit costs approximately 4114.9 coins when using this spear.
Before the Evolution of Combat, this weapon used to have a special attack, Spear Wall which damaged any unit that was in a 3x3 grid of the player and provided immunity to melee attacks for 5 seconds. In terms of actual effect, this rather resembles the Hurricane ability.
On the release of the EoC, this weapon used to have 'fast' speed but still the weapon damage of a 'average' speed weapon of the same level. This meant that Vesta's spear was much more powerful than its level suggested, with its damage (ignoring accuracy) more comparable to a lvl95 weapon. The speed was however changed to 'average' about 5 months after EoC's release.