Dictionary of Medieval Names
from European Sources

Gemma f. Latin gemma 'gem, precious stone'.

England
Latin
1240 Gemma (nom) StPaulDom p. 120
Italy
Latin
954 Gemma (nom) skinner p. 113; 1089 Gemma (nom) ibid. p. 115; 1348 Giemme (dat) INP 23
Cite as: J. Uckelman, S.L. Uckelman. "Gemma". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2016, no. 4. http://dmnes.org/2016/4/name/Gemma.