Mr J.L.B. Matekoni knew that he was right. The man spoke correct Setswana, but his accent confirmed the visible signs. Underneath the vowels, there were clicks and whistles struggling to get out. It was a peculiar language, the San language, more like the sound of birds in the trees than people talking.

He introduced himself, as was polite, and then he turned to Mma Ramotswe.

"This lady is now engaged to me," he said. "She is Mma Ramotswe, and I wish to buy her a ring for this engagement." He paused. "A diamond ring."

The jeweller looked at him through his hooded eyes, and then shifted his gaze sideways to Mma Ramotswe. She looked back at him, and thought: There is intelligence here. This is a clever man who cannot be trusted.

"You are a fortunate man," said the jeweller. "Not every man can find such a cheerful, fat woman to marry. There are many thin, hectoring women around today. This one will make you very happy."

Mr J.L.B. Matekoni acknowledged the compliment. "Yes," he said. "I am a lucky man." 

"And now you must buy her a very big ring," went on the jeweller. "A fat woman cannot wear a tiny ring."

Mr J.L.B. Matekoni looked down at his shoes.

"I was thinking of a medium-sized ring," he said. "I am not a rich man."

"I know who you are," said the jeweller. "You are the man who owns Tlokweng Road Speedy Motors. You can afford a good ring."

Mma Ramotswe decided to intervene. "I do not want a big ring," she said firmly. "I am not a lady to wear a big ring. I was hoping for a small ring."

The jeweller threw her a glance. He seemed almost annoyed by her presence-as if this were a transaction between men, like a transaction over cattle, and she was interfering.

"I'll show you some rings," he said, bending down to slide a drawer out of the counter below him. "Here are some good diamond rings."

He placed the drawer on the top of the counter and pointed to a row of rings nestling in velvet slots. Mr J.L.B. Matekoni caught his breath. The diamonds were set in the rings in clusters: a large stone in the middle surrounded by smaller ones. Several rings had other stones too-emeralds and rubies-and beneath each of them a small tag disclosed the price.