OLYMPIA PHOSPOR BRONZE STRINGS ARE AN ALLOY OF 90% COPPER AND 10% ZINC AND LAST LONGER THAN CONVENTIONAL BRONZE ALLOY STRINGS. ALSO, THE SMALL PERCENTAGE OF PHOSPOROUS IN THE ALLOY HELPS THEM TO RETAIN THEIR SOUND LONGER. THE STRINGS VIBRATE MORE CONSISTENTLY AND WITH GREATER AMPLITUDE TO PRODUCE A SHARPER, MORE PRECISE TONE.