Miss Benton's Beetle by Rachel Joyce

 I have to say that Rachel Joyce has an active imagination. I have read several books by her and each one is totally different. In Miss Benton's Beetle we meet Margery Benton, a tall, gawky woman who was raised by her aunts after losing both parents and all of her brothers. She doesn't consider herself remarkable at all except for a profound interest in beetles, spurred by her late father. She becomes obsessed with finding the mythical golden beetle of New Caledonia and sets off with a totally inappropriate assistant named Enid, who appears to be interested in the trip mostly to get out of England.

The two face more than their share of hardships but along the way a real friendship develops.