What symbols are preferred amoung certain demonimations more than others?
Christian Liturgical Colours vary somewhat amongst the various Christian denominations, yet most are relatively the same for the most part.
Methodists use a colour scheme similar to those used by Lutherans and Catholics, although the practice is not universally followed. The United Methodist Church, prior to the early-1990s, used red solely for Pentecost, even including the Sundays after Pentecost Sunday, with the use of green being reserved for the season of Kingdomtide, which usually lasted from late August/early September until Christ the King (the last Sunday in Kingdomtide). Since the publication of the 1992 Book of Worship, the UMC has followed the ELCA practice of wearing red only for Pentecost and Reformation Sunday and green for the rest of the Pentecost season.
The Presbyterian Church (USA), or its predecessor denominations, has sanctioned the use of liturgical colours and promoted their use in The Worshipbook of 1970, the 1993 Book of Common Worship and the 2018 Book of Common Worship. Advent and Lent are periods of preparation and repentance and are represented by the colour purple. The feasts of Christmas Day and Christmastide, Epiphany Sunday, Baptism of the Lord Sunday, Transfiguration Sunday, Easter Season, Trinity Sunday, and Christ the King Sunday are represented by white. Green is the colour for periods of Ordinary Time. Red is for Pentecost Sunday, but may also be used for ordinations, church anniversaries, and memorial services for ordained clergy. Red or purple are appropriate for Palm Sunday. During Holy Week, purple is used until the church is stripped bare on Maundy Thursday; the church remains stripped bare on Good Friday and Holy Saturday, though in some places black might be used on those days.
Similarly, the United Church of Christ includes indications of which liturgical colour to use for each Sunday in its annual calendar. The general Western pattern is followed, with either purple or blue recommended for Advent.
More on colour symbolism within Christianity can be found here: Color Symbolism in Christianity.
Crossed Keys are a Catholic symbol of papal authority.
According to Catholic teaching, Jesus promised the keys to heaven to Saint Peter, empowering him to take binding actions. In the Gospel of Matthew 16:19, Jesus says to Peter, "I will give you the keys of the kingdom of heaven, and whatever you bind on Earth shall be bound in heaven, and whatever you loose on Earth shall be loosed in heaven." Saint Peter is often depicted in Catholic and Eastern Orthodox paintings and other artwork as holding a key or a set of keys.
The keys of heaven or keys of Saint Peter are seen as a symbol of papal authority and are seen on papal coats of arms (those of individual popes) and those of the Holy See and Vatican City State: "Behold he [Peter] received the keys of the kingdom of heaven, the power of binding and loosing is committed to him, the care of the whole Church and its government is given to him [cura ei totius Ecclesiae et principatus committitur (Epist., lib. V, ep. xx, in P.L., LXXVII, 745)]". - Keys of Heaven
The Phoenix was a symbol of the resurrection according to some Early Church writers. This is also a recognized Catholic symbol for the resurrection, but many would not recognize it as such.
Several writings have been attributed to Clement, though most are believed to be spurious. However, he did leave one epistle that is widely considered to be genuine, a letter to a church in Corinth. It begins by saying that the delay in its sending from Rome was due to “sudden and successive calamitous events,” which appears to be a reference to the persecutions of the emperor Domitian. The date of the message is open to some debate, but if we make the assumption that Domitian’s persecutions ended with the emperor’s death, then it seems likely that it was written somewhere around 96 C.E.
The letter seems to have been a response to a situation in which some members of the Corinthian church rose up and deposed certain of their elders. Clement’s exhortations to return to former behavior are derived from both the Old Testament and examples drawn from the early church. This places him in an era when the Hebrew Scriptures were still providing definitive instruction for the conduct of the church, rather than being relegated to secondary status as they were by later generations. The letter is also concerned with reinforcing the truth of Jesus Christ’s resurrection and the hope of a future resurrection for human beings.
It is in this regard that we encounter a puzzling passage. In chapter 25, Clement writes: “Let us consider the strange sign which takes place in the East, that is in the districts near Arabia. There is a bird which is called the Phoenix. This is the only one of its kind, and lives 500 years; and when the time of its dissolution in death is at hand, it makes itself a sepulchre of frankincense and myrrh and other spices, and when the time is fulfilled it enters into it and dies. Now, from the corruption of its flesh there springs a worm, which is nourished by the juices of the dead bird, and puts forth wings. Then, when it has become strong, it takes up that sepulchre, in which are the bones of its predecessor, and carries them from the country of Arabia as far as Egypt until it reaches the city called Heliopolis, and in the daylight in the sight of all it flies to the altar of the Sun, places them there, and then starts back to its former home. Then the priests inspect the registers of dates, and they find that it has come at the fulfilment of the 500th year.” - The Phoenix and the Early Church
Herodotus, Lucan, Pliny the Elder, Pope Clement I, Lactantius, Ovid, and Isidore of Seville are among those who have contributed to the retelling and transmission of the phoenix motif. The phoenix symbolized renewal in general, as well as entities and concepts such as the Sun, time, the Roman Empire, Christ, Mary, and virginity. - Phoenix (mythology)
Many more Catholic symbols can be perused at the Catholic website: Fish Eaters.