It’s illegal to have large knives in Texas too like our famous Bowie Knives, unless you are engaged in an activity, in this case diving, a sporting activity, where such a knife would be considered appropriate.
But, yeah to just walk down the street with a double edged dive knife would be a no-no. Used while going to and from a dive site or at a dive site, totally legal in Texas. See below......
Texas - Health, Safety & Morals - 46.02. Unlawful carrying
weapons. (a) A person commits an offense if intentionally,
knowingly , or recklessly carries on or about his person a
handgun, illegal knife, or club. [Exceptions: official;
actor was own premises; was traveling; engaged in lawful
hunting, fishing, or other sporting activity; security
guard].
- 46.01. Definitions. (1) "Club"... includes... (D)
Tomahawk...
(6) "Illegal knife" means a:
(A) knife with a blade over five and one-half inches;
(B) hand instrument designed to cut or stab another by
being thrown;
(C) dagger, including but not limited to a dirk, stiletto,
and poniard;
(D) sword; or
(E) spear.
(7) "Knife" means any bladed hand instrument that is capable
of inflicting serious bodily injury or death by cutting or
stabbing a person with the instrument.