This course was presented by Dr. I Wayan Warmada on May, 3rd, 2014 at Mineral Resources Laboratory, Department of Geological Engineering Gadjah Mada University, Yogyakarta. Dr. I Wayan Warmada, from Gadjah Mada University, Yogyakarta explained about XRD (X-Ray Diffraction), including the meaning of XRD, the use of XRD and the explanation of clay mineral. Clay mineral is very difficult to be identified directly in the field, so it is necessary to microscopis observation. The microscopis observation was done by using XRD, from XRD will knew all of clay minerals type. This course held for 2 hours. Then after this there was another course by Mr. Fahmi Hakim, ST. Mr. Fahmi Hakim, ST is a student college who had graduated from Geological Engineering of Gadjah Mada University. He had minerals background knowledge, so he is very competent on it. Mr. Fahmi Hakim, ST explained about minerals various especially ore minerals such as gold and silver. On this course was held training of minerals appearance. Then the course was closed by photo sessions, sertificate and momento giving. Overall this course was successfully conducted, with about 20 participants attended this course, and all of them part of SEG members. The partisipants were very enthusiastic in listening to the explanation, and also gave a very good feedback by throwing many questions to the speakers.