Crystal

Real Name: Mr. Crystal James
First Appearance: Whiz Comics #15 (March, 1941)
Original Publisher: Fawcett
Created by: Ken Battefield

Origin 

Crystal James was the leader of a gang of thieves. He used "The Crystal" disguise to protect his identity when he attempted to kidnap his own millionaire ward, Ronnie Keller, and throw off suspicion when he forced her to sign over the enitre Keller Estate to himself. However, Ronnie was saved by the efforts of The Companions Three who eventually brought the Crystal to justice.

The Crystal was clever and extremely athletic, especially when making a getaway. He carried conventional weapons such as guns and knives, but he also enjoyed laying elaborate traps, such as "The Death Circle" which would kill anyone who entered it. On at least one occassion, he used a robot decoy to fool his opponents.

Golden Age Appearances: 

Master Comics #14

Whiz Comics #15

Diamond Jack

Real Name: Jack
First Appearance: Slam Bang Comics #1 (1940)
Original Publisher: Fawcett
Created by: Gus Ricca

Golden Age Origin:

Diamond Jack (last name never revealed) was given a ring with an inset magic diamond by an old magician. The magic diamond was later revealed to have been the lost eye-jewel of the god Khor from a temple in the Far East. The ring gave him the ability to create whatever he imagined and transmute objects. The ring also gave him super strength, invulnerability, super senses, the ability to heal others, limited flight, and a few other plot-convenient abilities. He used the magic ring to fight crime.

Golden Age Appearances:

Slam Bang Comics #1-7

Wow Comics #1