Nd x Gd 1−x Ca 4 O(BO 3 ) 3 (NdGdCOB) grown along the optimum phase-matching (PM) direction (θ=66.8°, Φ=132.6°) is reported for the first time in this paper. The utilization ratio of the as-grown crystals along the optimum PM direction is improved up to 95% when the optical devices were processed, while it is only 50% for the crystals grown along 〈010〉 direction. It often shows two large (150) facets and growth edge facets on the as-grown crystal surface. The small facets on the shoulders were determined as ( 2 ̄01) facets by X-rays. The ( 2 ̄01) edge facets will vanish and (010) edge facets will emerge when the crystal is tapered. The (010) edge facets which anchor at the three-phase-boundary (TPB) are the principal cause for the formation of (010) twins. Passive modulated Q-switched and mode-locking green laser operation at 530nm were achieved in NdGdCOB crystal using a xenon flash lamp as the pump source, Cr 4+ :YAG crystal as the saturable absorber with a plane-concave cavity, which is also reported here for the first time.