Origin and nature of sungulite

Sungulite is variety of serpentine finely to coarsely flaky, white with a silky luster. The term should be applied to coarse tabular serpentine (antigorite) in pseudomorphs on vermiculite. It is formed out of vermiculite and is surficial in origini occurring as a gradual replacement of vermiculite in lower parts of ancient weathering crusts of magnesian rocks with ferro-magnesian micas. It appears that the genetic relationships between kaolinite and halloysite are quite similar to those between sungulite and chrysotile. — J. J. Finney.