The olive tree has silver-green leaves, in the shape of an egg, and the lower side is white. The flowers are small, with a white-green colour and can be found gathered in large quantities during the flowering period of May and June.

Only a small percentage of the flowers actually becomes fruit due to abundant early falling. The fruit begins to develop during the summer and around September they reach the maturing phase. The exterior colour changes and becomes a matt, purple-blue colour. 

Complete maturing is reached, depending on the area, between November and March. Although the exterior appearance of the different species have determinate differences in dimension and characteristics, the olive fruit has a constant composition made of the hull and the pulp which contains approximately 70% oil and the stone from which the remaining 30% of the oil is obtained.

The oil begins to develop with the continuing ripening of the fruit and reaches its highest quantity when the olive oil reaches its most intense colour. Up until the beginning of maturation, olives do not contain oil but a sequence of organic acids and sugar.

At the end of ripening the composition of the olive is: 50% water, 20-24% oil, 20% carbohydrates, 6% cellulose, 1,5% proteins, 1,5% ash.