Starting the day at 1,111.70 points, Borsa Istanbul's BIST 100 index lost 14.62 points over Wednesday's close of 1,126.99 points.

On Thursday, the market was closed to observe the Republic Day on Oct. 29.

During the day, the index hovered between 1,102.57 and 1,120.85 points.

The total market value of the BIST 100 was around 823.1 billion Turkish liras ($101.35 billion) by market close, with a daily trading volume of 7.66 billion Turkish liras ($920 million).

On the last transaction day of the week, 16 stocks on the index rose, 83 fell, and one was flat compared to Wednesday.

The highest trading volumes were posted by state lender Industrial Development Bank (TSKB), and private lenders Sekerbank and Garanti.

Paper and carton producer Kartonsan was the best performer, with its shares up 10%, while stocks of telecommunications firm Alcatel dropped the most, losing 5.73%.

The price of one ounce of gold was $1,877.60 by market close, down from $1,900.25 at the previous close, according to data from Borsa Istanbul's Precious Metals and Diamond Markets.

The price of Brent crude oil was around $37.70 per barrel as of 6.15 p.m. local time (1515GMT) on Friday.