The bronze rooster was commissioned by Pope Leo IV from the 19th century and it was placed on the top of of the bell tower for the old Constantinian Basilica. Its significance is debated among historians. Some try to relate it back to the biblical story of "doubting St. Peter" where the rooster crowed three times after Peter denied Christ, but many dispute this relation to the tale. Scholars agree that the rooster's significance during Medieval times stood as a symbol of vigilance against evil and to announce the break of day after the darkness of night (saintpetersbasilica.org). This meaning might have been derived from ancient Greek beliefs of the rooster symbolizing victory over the night.
The Reliquary of the Holy Lance is from the 15th century and is made of a gold-plated silver mounting on a six-lobed base supporting a rock crystal sphere. The top resembles the lantern of a dome with six crystal elements. A reliquary is a container holding a sacred object. The Holy Lance refers to the lance that pierced Jesus' side when he was nailed onto the cross; it is also known as the Spear of Destiny or the Lance of Longinus. Strangely enough, the Catholic church makes no comment on the authenticity of the contents of the reliquary. There are claims by various other churches (Vienna, Echmiadzin, Antioch, etc.) that they have the original, but no one knows for sure which of the lances is real.
The Holy Lances in Echmiadzin and Vienna