===Higher than expected lithium in metal-poor stars===
Certain orangemetal-poor stars can also contain aan abnormally high concentration of lithium.<ref name="high">{{cite journal |doi=10.3847/2041-8213/aaa438|title=Enormous Li Enhancement Preceding Red Giant Phases in Low-mass Stars in the Milky Way Halo|journal=The Astrophysical Journal|volume=852|issue=2|pages=L31|year=2018|last1=Li|first1=H. |last2=Aoki|first2=W. |last3=Matsuno|first3=T. |last4=Kumar|first4=Y. Bharat|last5=Shi|first5=J. |last6=Suda|first6=T. |last7=Zhao|first7=G. |last8=Zhao|first8=G.|bibcode=2018ApJ...852L..31L|arxiv=1801.00090|s2cid=54205417 |doi-access=free }}</ref> ThoseThese orangemetal-poor stars that were found to have a higher than usual concentration of lithium tended to orbit massive objects—neutron stars or black holes—whose gravity evidently pulls heavier lithium to the surface of a hydrogen-helium star, causing more lithium to be observed.<ref name=emsley>{{Cite book|last=Emsley |first=J. |title=Nature's Building Blocks |publisher=Oxford University Press |___location=Oxford|date=2001 |isbn=978-0-19-850341-5}}</ref>
