The origin of spheroidal halloysites: a review of the literature. (2nd January 2018)

• Record Type: Journal Article
• Authors: Cravero, F.; Jock Churchman, G.
• Is Part Of: Clay minerals. Volume 51:Number 3(2016:Sep.)
• Page Start: 417
• Page End: 427
• Publication Date: 2018-01-02
• Subjects: spheroidal halloysite, -- allophane, -- iron content, -- microbes, -- organic matter, -- volcanic glass; Clay minerals -- Periodicals; Clay -- Periodicals; 549.6
• DOI: 10.1180/claymin.2016.051.3.13
• Languages: English
• ISSNs: 0009-8558

Abstract

Abstract: Tubular halloysite has many applications as a nanomaterial. Spheroidal halloysite (SPH) is the other most common form of halloysite. Its mode of formation has had different explanations, including association with allophane, or more generally, following weathering of volcanic glass. Some SPHs have formed from minerals in crystalline rocks, sometimes as an early stage of evolution into plates and/or tubes of halloysite and ultimately to kaolinite. Spheroidal halloysites can show a range of Fe contents and can occur with other forms of halloysite; they have often formed in confined environments whereas tubular halloysites apparently form in more open spaces. They have also formed on microbes or where there is a significant amount of organic matter. Generally, SPHs have often formed by rapid dissolution of volcanic glass and primary minerals. The SPHs can persist over time. They have fewactive edges, so interparticle interaction is poor, causing low viscosities in clay-water suspensions, poor soil stability and low adsorption capacities.