The Colorado CCW permit law pertains only to concealed handguns, not to any type of knife, even though my permit is actually titled "Concealed Weapon Permit". I think too much of 18-12-105(c) was omitted when quoted in the previous post.
"(c) A person who, at the time of carrying a concealed weapon, held a valid written permit to carry a concealed weapon issued pursuant to section 18-12-105.1, as it existed prior to its repeal, or, if the weapon involved was a handgun, held a valid permit to carry a concealed handgun or a temporary emergency permit issued pursuant to part 2 of this article; except that it shall be an offense under this section if the person was carrying a concealed handgun in violation of the provisions of section 18-12-214"
A knife with blade length of 3.5 inches or less may be concealed by any adult. Knives with longer blades may be openly carried.