Factual error: When Kirk is given the medicine badge, it's a stretchy elastic/Spandex headband. This is supposedly a completely pre-industrial culture paralleling the early Native American tribes. They have no fabric, no yarn, no spinning wheels - only hides and animal hair, neither of which can stretch a la Spandex.

Continuity: When Miramanee and her companion first see Kirk at the obelisk, the two women are standing, holding their fruit baskets, just inches from each other. In the very next, reverse angle shot, they're suddenly several feet apart.

Continuity: When Spock orders the phasers to fire, they shoot outward from the ship at an angle from each other, but when they hit the asteroid they converge at a single point.