  We report on the synthesis of a new $\gamma$-phase of the spin
$S$~=~$\frac{3}{2}$ compound SrCo$_2$(PO$_4$)$_2$ together with a detailed
structural, magnetic and thermodynamic properties. The $\gamma$-phase of
SrCo$_2$(PO$_4$)$_2$ crystallizes in a triclinic crystal structure with the
space group $P\bar{1}$. Susceptibility and specific heat measurements reveal
that SrCo$_2$(PO$_4$)$_2$ orders antiferromagnetically below $T_{\rm N}\simeq
8.5$\,K and the nature of ordering is three dimensional (3D). The magnetic
isotherm at temperatures below $T_{\rm N}$ shows a field-induced spin-flop
transition, related to the magnetocrystalline anisotropy, at an applied field
of $\sim$~4.5~Tesla. Remarkably, heat capacity shows magnetic-field-induced
transitions at $T_{\rm N1}$ = 3.6 K and $T_{\rm N2}$ = 7.4 K. The magnetic long
range ordering (LRO) is also confirmed in both the Knight shift and
spin-lattice relaxation rate ($1/T_{1}$) of the $^{31}$P-NMR measurements.
However, below the LRO we have not detected any NMR signal due to faster
relaxation. We have detected two structurally different phosphorous sites in
$\gamma$-phase of SrCo$_{2}$(PO$_{4}$)$_{2}$ and they shift differently with
temperature.
