Clare of Carmel was born in San Miguel, El Salvador, on October 12, 1857 to Carmen López and Daniel Quirós López. Her parents decided to consult the saints to choose the name of their daughter and discovered that the day was dedicated to Saint Clare of Assisi, so they did not hesitate to call her Clare of Carmel.

On October 31 of the same year, she received the sacrament of baptism in the church of Santo Domingo. When she was one year old, her parents separated and the girl was taken to Santa Tecla, a municipality in the La Libertad department of El Salvador, where she lived until her death.

In 1872, at the age of 15 and at the request of her mother, Chiara married the Costa Rican Félix Alfredo Alvarado, with whom she had six children; but at the birth of the last child she was abandoned by her husband. As a teenager, Clare was involved in church affairs. Over the years, she carried out humanitarian works and made known to other women the importance of serving God, the Virgin and their neighbour.

Seeing her charitable virtues, Monsignor Antonio Adolfo Pérez y Aguilar, Archbishop of San Salvador, allowed her to use the premises of the Belén monastery (the current Belén school in Santa Tecla) to work with poor and abandoned girls, declaring her, after she had set out on the path of a religious, as mother superior Clare Mary of Jesus.

On October 14, 1916, she founded the Third Order of the Discalced Teresan Carmelites of Saint Joseph. At the suggestion of Fr. Luke of Mary most Holy, former General of the Order of Carmel, the congregation took the name of Tertiary Carmelites of St. Joseph.

She died on December 8, 1928. Her remains are buried in the chapel of the Belén school.

On October 31, 2008, the decree of validity was granted to the Diocesan Inquiry into her «life, virtue and reputation of holiness».