Settlement here begins with a catastrophe. In 1833 a great wildfire swept the area and burned for roughly sixty days, and in the scorched ground behind it the caatinga — Brazil's thorny dry scrub — came surging back. The first settlers named their village for exactly that: Nossa Senhora da Conceição da Boca da Caatinga, Our Lady of the Conception at the Mouth of the Caatinga. The name kept changing as the place did. It became the Distrito de Caatingas in 1880, then Fortaleza in 1892. Emancipation as a municipality came in 1912. Not until 1943, on a suggestion from a resident named Nelson de Faria, did it become Pedra Azul — blue stone — the name that stuck.

In 1927, prospectors hit what the Portuguese of the mining country calls a bamburro — a sudden rich strike — of aquamarine at the Fazenda Laranjeira. Aquamarine is beryl, the same mineral family as emerald, tinted by traces of iron into every shade from pale sky to deep sea. Minas Gerais has yielded a great deal of it, but nothing anywhere has matched what Pedra Azul eventually gave up. The rough Dom Pedro crystal was so large that it was broken before it could be studied whole; from the surviving piece a single gem was cut, and no larger faceted aquamarine has been produced since. The stone left Brazil. The mines and the memory did not.

There is another Pedra Azul in Brazil, and it is the one most people picture: the striking granite peak in Espírito Santo, an hour or two inland from Vitória, that turns blue in certain light. This is not that place. This Pedra Azul is a working municipality of 1,595 square kilometres in the Jequitinhonha, its seat at about 617 metres, roughly 720 kilometres from Belo Horizonte. It does have its own rocks, and they are worth the confusion. Climbers and rappellers work the outcrops around town — Pedra Cabeça Torta, Pedra Forno de Bolo, Pedra da Conceição, Pedra da Montanha, Pedra da Rocinha. One of them is treated locally as the symbol of the city, and the view from the top runs a long way across dry country.

Brazilian statisticians use Pedra Azul as an organising unit, which tells you something about its standing out here. The town gives its name to a microregion that gathers Cachoeira de Pajeú, Comercinho, Itaobim, Medina, and Pedra Azul itself into one bureaucratic bundle inside the wider Jequitinhonha mesoregion. That is the kind of importance a place earns by being the one with the banks, the hospital beds, and the highway connection. There are ten health clinics and a hospital with 66 beds. There were two banking agencies as of 2006, and 58 tractors spread across the farms — roughly one for every ten of them. Numbers that modest are easy to read past. In a valley this dry and this far from the coast, they add up to a town other towns depend on.

The Jequitinhonha valley has a reputation in Brazil for hardship, and Pedra Azul carries some of it. The municipality's human development index stood at 0.660 at the 2000 measurement, ranking it 709th of the 853 municipalities in Minas Gerais. The 2022 census recorded 24,410 residents. Cattle raising and farming drive the economy: around 570 farms occupy the rural area with roughly 1,700 people working in agriculture, and the crops are bananas, coffee, passion fruit, beans, manioc, and corn. The heat and the dry are the constants — the thermometer has recorded 38.6 °C and, at the other extreme, 5.6 °C on a cold August morning in 1994. Rain, when it comes, comes hard; 134.2 millimetres fell in a single day in December 2021. The town sits 16 kilometres east of the BR-116, the Rio–Salvador highway, with the Bahia border 49 kilometres to the northeast.