Science is not one of my strong points so I'm not going to pretend by using long words that the causes of the crystallisation that sweeps the African jungle and Florida swamps is terribly clear to me.
However, the lack of complete understanding didn't detract from the enjoyment of the book because this is tapping into the usual Ballardian themes of society breaking down and the reaction of intelligent people to that collapse in social order.
As the jungle crystallises a former leper colony doctor heads back into the jungle not just to see the crystallisation process first-hand but also to reconnect with an old flame. On the boat up the river, a very Conradeque moment, the main character Dr Sanders notices another passenger, Ventress, who it becomes clear later on is on a similar mission to fight with a mine-owner for possession of his dying ex-wife.
The army is holding the line against expanding shimmering jewelled jungle but the main focus to start with is not to enter the jewelled zone but to work out just how the people on the edges of it can be liberated.
In a classic Ballardian way the choice then moves into a more crucial stage which is for the individuals to decide how they want to react to the prospect of life or death. A primeval urge seems to be driving some characters into the jungle into a world where death comes as the skin turns to crystals shimmering and glittering as the very breath it shut up inside the victim.
In a very graphical moment Sanders tries to save the life of an army officer who is crystallising by clearing his mouth by pulling off the crystals. Later on the edge of the affected zone he realises with horror his handiwork has maimed the officer ripping off his skin.
The choice for Sanders is to run, follow the example of his leprosy suffering former girlfriend and embrace the change or crystallisation. The army pulls out and the spread of the crystals continues to gather pace covering the trees and grasses in a shimmering blanket of sparkling frost.
For Sanders the pull back to the crystals and that sense of deciding to embrace the crystals is something that takes time. As a reader you are left sharing that indecision until the very end.
As you come to expect from Ballard the writing is tight, the cast selective and the attention to detail, making the whole thing plausible, is there in abundance. Personally I would run. But facing the pull of the strange lights and the impact on the mind who knows?
Just as with the Drowned World the actions of the main character cannot be logically explained. In a world that has been turned upside down perhaps the primeval instinct is over powering? Brilliantly described and Ballardian with a capital B this along with High Rise and Drowned World has to be one the books by him that is highly recommendable.