Volume 1 of this special issue of Lithos, dedicated to Roger Clement, presents papers describing the geology and emplacement of several of the recently discovered kimberlites in northern Canada in which diamond mines are now operating. Other papers are concerned with the petrography, age of emplacement, geochemistry and petrogenesis of kimberlites from Canada and other worldwide localities.

International Kimberlite Conferences (IKCs) are special events that are held across the world once in four to five years. IKC is the confluence platform for academicians, scientists and industrial personnel concerned with diamond exploration and exploitation, petrology, geochemistry, geochronology, geophysics and origin of the primary diamond host rocks and their entrained xenoliths and xenocrysts (including diamond) to get together and deliberate on new advances in research made in the intervening years. Ever since the organization of first IKC in 1973 and its tremendous success, the entire geological world eagerly look forward to subsequent such conferences with great enthusiasm and excitement. The scientific emanations from IKCs continue to make significant impact on our understanding of the composition, nature and evolution of the planet we live on. The previous conferences were held at Cape Town (1973), Santa Fe, New Mexico (1977), Clermont-Ferrand, France, (1982). Perth, Western Australia (1987), Araxa, Brazil (1991), Novosibirsk, Russia (1995), Cape Town (1998), Victoria, Canada (2003) and Frankfurt, Germany (2008). The tenth IKC was held at Bangalore, India between 5th and 11th February 2012. The conference was organized by the Geological Society of India in association with the government organizations, academic institutions and Indian diamond mining companies. About 300 delegates from 36 countries attended the conference and 224 papers were presented. The papers include 78 oral presentations and 146 poster presentations on following topics: Kimberlite geology, origin, evolution and emplacement of kimberlites and related rocks, petrology and geochemistry of metasomatised lithospheric mantle magmas, diamond exploration, cratonic roots, diamonds, diamond mining and sustainable developments and policies and governance of diamond exploration. Pre- and post-conference field trips were organized to (i) the diamond bearing kimberlites of Dharwar Craton in South India, (ii) lamproites of Bundelkhand Craton in northern India and (iii) diamond cutting and polishing industry of Surat, Gujarat in western India. A series of social and cultural programmes depicting cultural diversity of India were organized during the conference. The Kimberlite fraternity enjoyed yet another socially and scientifically successful conference.

Given the established nature of geoscientific knowledge of the Kaapvaal craton compared to the Slave craton, and given the exciting new interdisciplinary results coming from the Kaapvaal Project and from Slave craton studies, scientists working on both cratons were brought together in a workshop to compare and contrast the nature of these two cratons. Of the 54 papers presented at the workshop, 24 are included in this volume. There are clearly major similarities and differences between these two Archean cratons. The crust of both was predominantly formed in the Mesoarchean. Both contain crustal sections consisting of terranes of different ages welded together by Archean accretionary events. Both crustal sections are underlain by lithospheric mantle sections consisting of peridotites that experienced extensive partial melt extraction between 2.9 Ga and 3.2 Ga, but this is where the similarities between the cratons end. One of the most striking differences between the Slave and Kaapvaal cartons is the apparent seismic homogeneity of the Kaapvaal craton's SCLM whereas the Slave craton is seismically layered. The seismic layering in the centre of the craton correlates laterally and with depth with electrical layering and geochemical layering. Taken together, these differences suggest that SCLM formation was different for the two cratons, implying that the search for a single causative formation process is bound to fail. Reprinted from the journal Lithos Volume 71, numbers 2-4.

Volume 2, dedicated to Barry Hawthorne, presents papers concerned with the genesis of eclogites, the mineralogy of diamond and its inclusions, exploration methods for kimberlite, the geochemistry of the upper mantle and the character of cratons.

Diamonds in Nature: A Guide to Rough Diamonds illustrates the range of crystal shapes, colours, surface textures, and mineral inclusions of rough, uncut, naturally forming diamonds. Each chapter contains photographs that show the unique physical characteristics of the diamonds, and the accompanying text describes the processes that led to their formation. This book is an invaluable reference manual for professional geoscientists—including gemmologists and exploration geologists.

The nature and origin of the small-scale volcanic systems, generally referred to as 'monogenetic', have enjoyed an elevated level of interest during the past decade. There has been recognition that their ostensibly simple volcano types are a window into the nature of explosive volcanism, landscape evolution and the processes of magma generation in the Earth’s upper mantle. In the past few years, major conferences have offered specialized technical sessions dealing with monogenetic volcanism and there have been thematic conferences, such as the IAVCEI International Maar Conference series, which have provided a focus for discussion of volcanological and geochemical aspects of small-scale basaltic volcanism. Many new aspects of monogenetic volcanism have emerged and have clearly demonstrated that this volcanism can be very complex on a fine scale. This book is a collection of papers arising from two recent Maar Conferences (the fifth in Queretaro Mexico and the sixth in Changchun, China) and serves as a snapshot of current research on monogenetic volcanism.