English: The top of the shield is a very special design unique to the LA diocese. While they are somewhat different in color and artistic style for each bishop, all of the LA bishop coat of arms have this unique element. This emblem represents a very rare event in the life of the church: an episcopal ordination which takes place in the titular of a cathedral, within a diocese, and within a city. All three elements have the same name: Our Lady of the Angeles.

For Bishop Nunes’ design, the top of the shield is blue, representing our Blessed Mother and her love for her Son and His Church, and a Fleur de Lys, the universal symbol for the Mother of Christ. One fun fact about the Fleur de Lys is that it is Catholic heraldry, it is the only symbol which universally represents every title and role of the Blessed Virgin Mary.

This coat of arms is divided into a chevron pattern chosen specifically for the themes desired by Bishop Nunes. The space inside the chevron field is rendered in red which in Catholic heraldry is symbolic of deep love, particularly the Sacred Blood and filial love for Christ by us and His abundant love for us. It also historically represents the color of the Pacific Rim region, where the bishop’s parents began their journey to a new life in the United States.

Also in this field is found a Chinese emblem specifically requested by Bishop Nunes, which honors his roots in Macau and Hong Kong. The Chinese junk (aka Chinese sailing ship) is in gold representing God’s eternal goodness.

For all bishops, the episcopal cross only has one transverse arm. The cross may be jeweled or depicted as plain and most resemble the processional cross commonly used in liturgies. Bishop Nunes’ episcopal cross is worked in gold with a gemstone, known as the Chrysoberyl, which is the national stone of Portugal, to represent his Portuguese heritage.

Source: https://lacatholics.org/bishop-nunes-coat-of-arms/