This report presents briefly and qualitatively the result of geophysical work on the Lammin iron deposits in Piddig, Ilocos Norte as a follow-up to the apparently encouraging results of the survey conducted by Hunting Geophysics Limited (1954) and the geological investigation done by the Philippine Bureau of Mines (J. C. Fernandez, 1962), respectively. These factors have initiated the ground magnetic survey as the basic and indispensable technique to help in the scientific exploration of the area with magnetometer and dip needle.

As far as the author can remember, there has never been a dip needle survey of any deposit in the Philippines. For this reason, the use of dip needle at this instant has a dual purpose: (1) for academic purposes and (2) for assessing its applicability in prospecting for iron deposits in the Philippines.

The Lammin deposit is within the municipality of Piddig, Ilocos Norte and Apayao, Mt. Province and is about 35 kilometers east-northeast of Piddig town (plate I). It is accessible by a combination of road and foot trail. The average elevation of the mineral ized area is approximately 900 meters above sea level. It is covered with pine trees, cogon and other faunal species that usually grow at this elevation.

Fieldwork was confined primarily within the mineralized belt which has an area of approximately 5 square kilometers and lasted for three months from March to May, 1963. The geological and geophysical surveys were done by the author with the assistance of B. Vera Cruz and O. Abarquez, both geologists of the Bureau of Mines, while the grid survey was done by V. Casco, surveyor of the Mineral Lands and Topographic Survey Division.