Ayurveda is the ancient medical science of India. Many herbal, mineral and metallic drugs are being successfully used in treatment of various ailments. Diamond (Hiraka) in a form of medicine sounds strange, but incinerated precious stones (Ratna Bhasma) has important role in Ayurvedic medicines. Medicines made from Diamond are used by some Ayurvedic physicians in various Cancers; and it has reported encouraging results. To evaluate the clinical efficacy of Hiraka Bhasma (Ayurvedic Diamond preparation) in Carcinoma, clinical study with pre-diagnosed patients of carcinoma was carried out; and the same is principle subject of this book. This book elaborates review of ancient texts related to medicinal use of Diamond, pharmaceutical processing of Diamond and its clinical study. This book will definitely be useful for Ayurveda clinicians and researchers.