The word “Archangel” is mentioned twice in scripture. It is a Greek word: “Archaggelos”. “Arch” meaning “first” and “Aggelos” meaning “messenger”. An “Archangel” is basically said to be the leader of each set of angels as there are said to be angels for different purposes that relate to both heaven and earth. 
In Christianity, whether in the Catholic or the Protestant Bible, the term "archangel" appears only twice: in Jude 1:9, where it is applied to Michael, and in 1 Thessalonians 4:16, where it is used generically or, according to Jehovah's Witnesses, of the Lord. Michael and Gabriel are recognized as archangels in Judaism, Islam, and by most Christians . No one truly knows how many Archangels there are. Some faiths have identified a group of secen Archangels, but the actual angels vary, depending on the source. Mostly, the Archangels referred to in religious texts are, Raphael, Gabrieland Michhael; the other archangels vary, but most commonly include Uriel as well.
It is believed that in certain times of need if the Archangels are called upon they will assist you with your problems and everyone is said to have their own Guardian Angel who can then connect to the higher realms. These Angels are said to stand around God’s throne ready to carry out the most important duties to human beings. They are said to watch over us consistently. Although there is some debate over whether or not there are Seven Arachangels in full the other Archangels are still mentioned in historical and religious texts. What is also interesting is the number 7 is considered an extremely spiritual number.
For example, 
from the Seven Days of Genesis to the Seven Seals of Revelation, Scripture is saturated with the Number Seven. Essentially all Biblical scholars, regardless of their stance regarding the meaning of numbers in Scripture, have recognized its special symbolic significance. Simply stated, and is said to be impossible to miss. God laid the foundation of its meaning when He introduced this number in the context of His finished Work of Creation (Gen 2:2f): “And on the seventh day God ended his work which he had made; and he rested on the seventh day from all his work which he had made. And God blessed the seventh day, and sanctified it because he had rested from all his work which God created and made”.
Also, in Scripture, seven symbolizes completeness or perfection. On the seventh day God rested from his labours and creation is finished (Gn 2:2). We even see Archangels echoed in fairytales, for example “Snow white and the Seven Dwarfs” who all stood by her and protected her. Also, in Numerology, the life path of someone who has fallen on number 7 often takes on the personality as the “seeker of truth” and these people are often found to be very spiritual but not necessarily religious.
Many New Age beliefs have become fanatical about Archangels are use the energy for healing which also ties in with colour healing and the spiritual practice “Reiki” as each Archangel is said to represent a specific ray of colour as stated below:
( It has been said that a good way to envisage the Archangel’s rays of colour is to imagine the Northern lights shining brightly in the sky). The Archangels Archangel Michael
is the first who is said to represent the colour blue. He is the angel of protection and is the first angel to be called upon when you fear any kind of harm or danger. Archangel Jophiel
is said to represent the colour yellow. He holds much wisdom and he is full of knowledge, inspiration and clear seeing. He can heal away wounds and help those who are suffering from past hurts or addictions. Archangel Chamuel
is said to represent the colour pink. This Archangel is very kind, caring and loving and is full of compassion. He can also be very creative and is there to help you with your love questions. He can also help you to forgive and balance self esteem. Archangel Gabriel
is said to represent the colour white. This Archangel can help with guidance and spiritual matters of your heart. He is pure and open and is also known to help with financial concerns. Archangel Raphael
is said to represent the colour green and he will help you to speak your truth from matters of the heart. He can be very practical and is a fighter! He would be great guidance for work or education issues or those that work in the armed forces. Archangel Uriel
is said to represent the colour gold. He is there to help you tune in to your own inner peace and can promise you much hope through very trying times such as wars or family discrepancies. Arhcangel Zadkiel
is said to represent the colour violet. He can help you to release painful memories and can also assist you on your path for justice or clarity. This Archangel can help you also to tap into your own intuition.
Now that you have a brief understanding of the Archangels and their colours you may find it useful to refer to each one in your time of need, depending on what it is, you could hold a crystal in your hand to represent each ray that the Archangel carries.
With love and light x x x