Abstract
The study of mineral surfaces has been revitalised by the application of Atomic Force Microscopy to problems of nucleation and growth. In situ observations of crystal growth of BaSO4 and SrSO4 in a fluid cell in an Atomic Force Microscope (AFM) reveals the role of the crystal structure of the substrate in controlling spiral growth and two-dimensional nucleation. The growth of solid solution crystals is considerably more complex. The variation of the supersaturation of a given aqueous solution with respect to each solid composition leads to the possibility that different compositions can simultaneously grow by different mechanisms on the same crystal face. These predictions are compared with direct AFM observations of crystal growth of the (Ba, Sr)SO4 solid solution.
