Doctor Marjorie Devarona was a blonde haired Human female, one of the Federation's leading archaeologists and an old friend of Jean-Luc Picard.
In 2368 she discovered the ruins of an ancient city on Rajatha Prime. The planet's unique ionosphere prevented accurate scans being taken from orbit so the team she lead had to resort to more traditional detective techniques to explore the ruins.
Devarona invited her old friend Jean-Luc Picard to join the expedition. Shortly after he arrived the team discovered the remains of a 22nd century shuttlepod and near it the corpses of those who had piloted it and the valuable harmonic diamonds they possessed. Unknown to the team at the time the diamonds emitted low-level energy waves which stimulated areas of the brain associated with primitive emotions, including anger, envy and greed, these emotions soon surfaced in the group. The night of the discovery whilst the group discussed what they might do with the profit's of their finds Devarona expressed a desire to use her share to fund archaeological digs all over the quadrant. Each team member went to bed with a diamond in their care.
Unfortunately by the next morning Devarona was dead, killed by Gest, a member of the expedition who pushed her into a gorge and stole her diamond. As greed and paranoia engulfed the group the killings spread and by the end of the affair only Gest and Picard remained. The diamonds with no registered owners fell into the possession of Picard who, per Devarona's final request, had the Daystrom Institute finance digs all over the quadrant. (TNG comic: "Captain's Pleasure")