We observe two metal-poor main sequence stars that are members of the recently-discovered Sylgr stellar stream .
We present radial velocities , stellar parameters , and abundances for 13 elements derived from high-resolution optical spectra collected using the Magellan Inamori Kyocera Echelle spectrograph .
The two stars have identical compositions ( within 0.13 dex or 1.2 \sigma ) among all elements detected .
Both stars are very metal poor ( [ Fe/H ] = -2.92 \pm 0.06 ) .
Neither star is highly enhanced in C ( [ C/Fe ] < +1.0 ) .
Both stars are enhanced in the \alpha elements Mg , Si , and Ca ( [ \alpha /Fe ] = +0.32 \pm 0.06 ) , and ratios among Na , Al , and all Fe-group elements are typical for other stars in the halo and ultra-faint and dwarf spheroidal galaxies at this metallicity .
Sr is mildly enhanced ( [ Sr/Fe ] = +0.22 \pm 0.11 ) , but Ba is not enhanced ( [ Ba/Fe ] < -0.4 ) , indicating that these stars do not contain high levels of neutron-capture elements .
The Li abundances match those found in metal-poor unevolved field stars and globular clusters ( \log \epsilon ( Li ) = 2.05 \pm 0.07 ) , which implies that environment is not a dominant factor in determining the Li content of metal-poor stars .
The chemical compositions of these two stars can not distinguish whether the progenitor of the Sylgr stream was a dwarf galaxy or a globular cluster .
If the progenitor was a dwarf galaxy , the stream may originate from a dense region such as a nuclear star cluster .
If the progenitor was a globular cluster , it would be the most metal-poor globular cluster known .