First published in 1996, this volume has been substantially updated to reflect new research in the conservation of stone monuments, sculpture, and archaeological sites.

The design of treatments for the conservation of stone in historical buildings and works of art is a challenging task, as a deep understanding of the working properties and performance of the available products and methods is required to tackle complex decay patterns. The chapters in this book illustrate the state of the art on traditional and innovative materials and methods for stone conservation, examining current trends and future perspectives. Each of them is focused on describing the consequent phases that complement the spectrum of the conservation intervention: preliminary investigations, condition assessment, and mapping of the deterioration patterns; surface cleaning, with a specific focus on laser technology; consolidation; protection; repair mortars and grouts; and onsite assessment and monitoring of conservation treatments. The performance of the applied conservation interventions is criticized and discussed with an aim of providing the specialists with specific tools for stone conservation. This book intends to bridge the gap between laboratory studies and conservation interventions, by linking together the diverse scientific areas involved in the preservation of stone heritage. Different case studies are included, highlighting specific conservation challenges and their solutions in order to understand and overcome them. The aim is to guide conservators, conservation scientists and heritage stakeholders in the selection of compatible and sustainable materials and techniques for Conserving Stone Heritage.

It has become obvious that public policy will play a critical role in determining what portion of our architectural heritage will be passed on to future generations and what portion will be lost to deterioration, development, and natural hazards. In developed nations, as much as 10% of the built environment is deemed of sufficient cultural and historic importance to be given local or national listing. At the international level, UNESCO maintains a World Heritage List that includes many stone monuments. While the past two decades have witnessed a growing body of research devoted to understanding the fundamental mechanisms of damage to stone and to developing strategies for the conservation of stone, virtually no research has been conducted on the quantification of the economic role of stone buildings and structures as well as the valuation of cultural property. In order to introduce the tools and methods of economic analysis to the public policy debate on the preservation of cultural property, a multidisciplinary team of physical scientists worked with social scientists to explore how societal, economic, and ethical considerations might be integrated with technological options to lead to informed policy decisions. Recognizing that economic analyses must rest on firm technical data and sound conservation options, the state of our knowledge of mechanisms and rates of damage, the diagnosis of condition, and the evaluation of treatment options were subjected to critical review; special attention was given to the identification of promising, innovative areas of research. This volume represents an important first step in rationalizing the decision-making process for the setting of public policy in the preservation of our architectural heritage. It will be of interest not only to those actively engaged in research and conservation on stone structures, but also to those concerned with urban planning, public policy, economic analysis, and environmental standards setting. Goal of this Dahlem Workshop: to identify critical gaps in our knowledge of the deterioration mechanisms for treated and untreated historically important stone; to suggest innovative approaches to the study of deterioration mechanisms and novel remedial measures for treated and untreated historically important stone; and to address the socioeconomic factors that determine preservation actions for our architectural heritage.

Coping with Biological Growth on Stone Heritage Objects: Methods, Products, Applications, and Perspectives offers hands-on guidance for addressing the specific challenges involved in conserving historical monuments, sculptures, archaeological sites, and caves that have been attacked and colonized by micro- and macroorganisms. The volume provides many case studies of removal of biological growth with practical advice for making the right choices. It presents detailed and updated information related to biocides and to alternative substances, features that will be valuable to dealing with these challenges. The author’s goal is to provide access to information and offer the conceptual framework needed to understand complex issues, so that the reader can comprehend the nature of conservation problems and formulate her/his own views. From bacteria to plants, biological agents pose serious risks to the preservation of cultural heritage. In an effort to save heritage objects, buildings, and sites, conservators’ activities aim to arrest, mitigate, and prevent the damages caused by bacteria, algae, fungi, lichens, plants, and birds. Although much has been learned about these problems, information is scattered across meeting proceedings and assorted journals that often are not available to restorers and conservators. This book fills the gap by providing a comprehensive selection and examination of international papers published in the last fifteen years, focusing on the appropriate methods, techniques, and products that are useful for the prevention and removal of micro- and macroorganisms that grow on artificial and natural stone works of art, including wall paintings. Results on new substances with antimicrobic properties and alternative methods for the control of biological growth are presented as well. The book also emphasize issues on bioreceptivity of stones and the factors influencing biological growth and includes an outline of the various organisms able to develop on stones, a discussion on the bioprotection of stones by biofilms and lichens, a review of the main analytical techniques, and a section on bioremediation. This volume will be a valuable reference for cultural heritage conservators and restorers, scientists, and heritage-site staff involved in conservation and maintenance of buildings, archaeological sites, parks, and caves.

Heritage stones are those stones that have been used for many years, even centuries, to build the historic buildings and monuments of places around the world. Some of these stones are still being used for construction, but others are no longer used, either because quarries were exhausted or closed or because architects and constructors do not know about their particularities and importance. Several scientific papers discuss many of these stones, and a number of papers are currently being prepared, but this book is the first to emphasize the importance and significance of natural stone in the construction of a city, Salamanca, recognized as a World Heritage Site by UNESCO since 1988. In light of this recognition, Salamanca has a duty to preserve all historic buildings that make up the city by restoring those that are starting to deteriorate centuries after their construction. This book describes the buildings, the stones (all quarried centuries ago in the surrounding area), and the stone quarries, some of them inactive for many years, but that should still allow extraction of blocks on demand to restore and replace damaged specimens in the buildings, preserving the very character that saw the city receive recognition by UNESCO in the first place. There are many other places around the world that should follow this initiative and disseminate the importance of their heritage stones. This book will be of interest to professionals and academics in Geology, Engineering, architectural and artistic work in stone, both construction and conservation, but also to the general public.

This book is made up of contributions dealing with heritage stones from different countries around the world. The stones are described, as well as their use in vernacular and contemporaneous architecture. Heritage stones are those stones that have special significance in human culture. Examples include some very important stones that have been either neglected because they are no longer extracted, or stones that have great significance in commercial terms but knowledge of their national and/or international heritage has not been well documented. In this collection of articles, we have tried to spread awareness of architectural heritage around the world, the natural stones that have been used in its construction, and the need to preserve historical quarries that once provided the source of such stones. Historical quarries are linked to regional culture and tradition. Because of the specific technical and aesthetical characteristics of heritage stones, which have lasted for centuries, these historical quarries should be preserved to be able to use the stones for the proper restoration of monuments and historical buildings to avoid negative actions that can be observed in many places in the restoration of buildings, which are some times part of World Heritage sites. The final intention of this book is to continuosly grow the interest on this fascinating subject of heritage stones.

Heritage stones are building and ornamental stones that have special significance in human culture. The papers in this volume discuss a wide variety of such materials, including stones from Europe, Asia, North and South America, Africa and Australia. Igneous (basalt, porphyry, granite), sedimentary (sandstone, limestone) and metamorphic (marble, quartzite, gneiss, soapstone, slate) stones are featured. These have been utilized over long periods of time for a wide range of uses contributing to the historic fabric of the built environment. Many of these stones are of international significance, and so are potential Global Heritage Stone Resources, that is stones that have the requisite qualities for international recognition by the Heritage Stones Subcommission of the International Union of Geological Sciences. The papers bring together diverse information on these stones ranging from their geological setting and quarry locations to mechanical properties, current availability, and uses over time. As such the papers can serve as an entry into the literature on these important stones.