We analyse publicly available , individual spectra of four , massive ( M > 10 ^ { 11 } M _ { \odot } ) early-type galaxies with redshifts in the range 1.4 \leq z \leq 2 to determine their stellar content , extending our previous work up to z \sim 2 .
The wide wavelength range of the VLT/X-Shooter spectroscopic data in the UV-Optical-NIR arms along with the availability of spectro-photometry allows us to explore different techniques to obtain the stellar population properties , namely through age/metallicity sensitive spectral indices , full spectral fitting and broad-band photometric fitting .
Moreover , together with the widely used optical Lick indices we consider further indices in the UV rest-frame , and demonstrate that UV indices significantly help the accuracy of the resulting population parameters .

We find galaxy ages ranging from 0.2 to 4 Gyr , where the oldest galaxy is found at the lowest redshift , with an excellent agreement between ages determined via indices , full spectral fitting or broad-band colours .
These ages are in perfect agreement with ages of local galaxies at the same velocity dispersion when we assume pure passive evolution .
Total metallicities derived from indices show some scatter ( between less than half-solar to very high values , ( [ Z / H ] \sim 0.6 ] ) .
We speculate on possible mechanisms explaining these values , but given the sample size and low S / N of the spectra no conclusion can be made .

Indices in the UV-rest frame generally lead to similar conclusions as optical indices .
For the oldest galaxy ( 4 Gyr ) we show that its UV-indices can only be explained by stellar population models including a UV contribution from old stellar populations , suggesting that old , UV bright populations start to inhabit mature galaxies of a few Gyr of age .
This is the highest redshift ( z \sim 1.4 ) detection of the UV-upturn up to date .