While assessing the foundation of the Alamo Long Barrack last summer, Pam Rosser discovered a pigment fragment on the west wall of the structure facing the Cenotaph.

“We know that the walls of the missions Concepción and San Jose were beautifully painted, so why wouldn’t the Alamo also be decorated?” the Alamo conservator wondered during a recent interview in her office above the Alamo gift shop. “Actually, I had always wanted to do work on the Alamo façade, but because it’s such a popular place for people to take photos, the time never seemed right.”

The time is right now. For the next month, Rosser, conservator of the Alamo for 20 years, will be up on a scissor lift in front of the Alamo, ruining selfies, and chipping fragments of stone the size of a pinky nail with an X-acto knife. “Pigment harvesting,” she calls it.

Alamo Conservator Pam Rosser in her office. Credit: Courtesy / Steve Bennett

The slivers will be set in a polymer resin and analyzed microscopically for traces of pigment; in fact, Rosser already has discovered red pigment traces under the lower window on the north side of the façade, to the left facing the front entrance.

She speculates the window may have been bordered with small color blocks – “almost like mosaic tiles” – similar to those that surrounded windows at Concepción. The original white plastered façade – since largely worn away – may have been decorated with patterns or imagery in colorful lime washes as well.

“I do think it was decorated, at least in the areas where the columns and niches are,” Rosser said. “The colors would’ve been very bright when new – not opaque because they were washes – but the color would’ve stood out and caught your eye. It’s difficult to say what the design was; it’s another of the Alamo’s mysteries.”

The five missions – built by Franciscan missionaries in the 18th century, beginning with Mission San Antonio de Valero, or the Alamo –  “illustrate the Spanish Crown’s efforts to colonize, evangelize, and defend the northern frontier of New Spain,” according to UNESCO (United Nations Educational, Scientific and Cultural Organization), which named the missions a World Heritage site in 2015.

“The San Antonio Missions are also an example of the interweaving of Spanish and Coahuiltecan cultures, illustrated by a variety of features, including the decorative elements of churches, which combine Catholic symbols with indigenous designs inspired by nature,” according to the UNESCO website.

One example might be large floral designs on two interior walls of the Alamo sacristy, which can only be seen with ultraviolet light when the room is dark.

“We’ve found portions of a plant or flower, but we haven’t been able to determine the color or the shape of the blossoms,” Rosser said. “So, it makes you wonder what might have been on the exterior of the building.

“If you think about it, they wanted the Native Americans to connect to Catholicism, so why not make the buildings inviting? Wouldn’t you be more likely to be impressed with vibrant colors than just white? I would be, but maybe that’s just my personality.”

Alamo Conservator Pam Rosser harvests stone samples from the Alamo facade to test for traces of pigment. Credit: Courtesy / Steve Bennett

The conservator believes Spanish missionaries brought materials to make colors – vermillion, copper green, red and yellow ochre – with them to the New World “to create these elaborate and beautiful missions.”

The builders – teams of priests and artisans with specialties in architecture, stone-carving, engineering, all under the eye of the Spanish viceroy – used native limestone to build the missions. The stone for Concepción, for instance, was quarried on-site.

“We don’t know where the Alamo stone came from,” Rosser said. “Some think it may have come from the area at Sunken Garden or the Botanical Center. We know so much more about the construction and finishes of other missions, but not the Alamo, and it was the first one.”

Best known as the site of the 1836 battle, the Alamo has a colorful history. With roots dating back to the early 1700s, construction of the chapel we know as the Alamo began in 1758. Built using thick limestone blocks, it was probably intended to look like other missions, with bell towers and a dome.

“A relieving arch on the interior walls over the baptismal and the confessional tells us that a bell tower or other structure was planned,” Rosser said.

Historians believe the church was meant to be highly decorated, as evidenced by the niche and column carvings around the chapel’s front entrance.

But the structure was never finished, perhaps due to competition for funds and workers at the other missions as well as the construction of San Fernando Cathedral (1738-50).

“They didn’t need this church because they had this new fancy church just a short distance away,” Rosser said.

The gracefully curved parapet, which gives the Alamo distinction, wasn’t added until the 1850s when the U.S. Army put a new roof on the structure. The church was secularized in 1793, paving the way for it to become a military installation, which it largely was for nearly a century until Fort Sam Houston was established in 1876.

It was a mercantile operation – basically a wholesale general store – before the Daughters of the Republic of Texas was formed in 1895 with the mission of preserving the Alamo.

The current harvesting of pigment is another piece of the Alamo puzzle, Rosser said.

“It will tell us more about the mission era – and people forget that the Alamo was a mission first,” she said.

Just across the San Antonio River from the historic settlement known as La Villita, the Alamo complex was a self-sufficient village unto itself, with residences at its high point in 1744 for 300 American Indian converts, workshops, and surrounding acreage for grazing cattle and sheep and growing corn and cotton.

And yet, the Alamo in some ways remains a work in progress.

“There’s just so much we don’t know about the Mission San Antonio de Valero that is yet to be discovered or resolved,” Rosser said. “This is another step in that exploration.”

Steve Bennett has written about arts and culture in San Antonio for more than 30 years.