Nana Ekua Brew-Hammond was reading the Bible one day, and she got to a part about the Temple of Solomon that made her pause.
There were some drapes in the temple that were blue.
"And I was wondering why that was significant," says Brew-Hammond. So she started researching, and learned an interesting tidbit about a species of snail.
She learned dyers in Mexico would press the snail's foot. In the Middle East, they cracked its shell. The snail produced secretions which, when oxidized, turned blue.
"And this was used to dye the temple drapes, and also textiles of that time. And it was very expensive because a snail produced only one drop," says Brew-Hammond. "So I was like 'Woah! Kids need to know about this!'"
Blue traces the color through time and around the world: from Afghanistan's lapis lazuli, made into jewelry, ground to create eye shadow and paint, to the indigo plant grown on plantations in India and Bangladesh, soaked in water and used to dye fabric. In Italy, Brew-Hammond writes "from the 13th century onward, some artists began reserving blue to paint the robes of Mary, the mother of Jesus."
Blue was illustrated by Daniel Minter, who says he uses the color in most of his work. "It's my go-to color. A deep, deep blue," he says. "A lot of the people in my paintings have tones of blue within the skin. And I use that to show the depth of color within our skin. And that beautiful blue that goes straight all the way to black."
Minter would have loved to use some of the materials referenced in the book, like lapis lazuli, but didn't think they would photograph as well, so settled on acrylic paint for the illustrations. He says it's impossible to count the number of blues in this book.
"I just did wash after wash after wash of blues. And I would layer those blues making them deeper, leaving some of them lighter and introducing other colors to them," Minter says.
Since there is no main character in Blue, other than the color itself, Minter says he focused on illustrating the human interaction with the color. He began with the hands.
Hands reaching up to the sky. Hands hovering over a bowl of blue powder. Hands cradling a snail shell. Hands holding a piece of indigo-dyed fabric.
Blue is Nana Ekua Brew-Hammond's first children's book. She says it was not a conscious decision to go without a main character - she and Daniel Minter worked separately on this story.
"I'm so glad that was the process," Brew-Hammond says. "I think that it's a good thing that we were each able to work in our silos because when it came together... when I saw the final product, I was like 'wow.'"
Minter, who previously illustrated the Caldecott Honor book Going Down Home With Daddy, says he also likes working separately from the author.
"I don't want to talk to the author about the book because I want to trust the text," he says.
And — Minter adds — he also wants to insert some of himself into the book. In Blue, Minter is the hands reaching up to the sky, and the kids soaring towards the clouds.
"I often wondered when I was a child, how can I get up to the sky? How can I get up there and touch it?"
And, even though she and Minter hadn't met or spoken to each other about the book — Brew-Hammond found herself in the illustrations, as well.
"It felt really beautiful because I remember myself as a little girl. I had a lot of embarrassment about being from Africa and being from Ghana," says Brew-Hammond. "Seeing this little girl on the cover, so proud in her blue... it was like me, but not having that shame of the past."
Today, of course, there are chemical blues. As Brew-Hammond writes, "In 1865, scientist Adolf von Baeyer began trying, and forty years later, in 1905, he won the Nobel Prize for creating a chemical blue."
But for many years, blue remained very difficult to produce.
"Quality was something that was also really important," says Brew-Hammond. As artists tried to re-create the color of the sky, or the ocean, if they got their blue from petals, for example, the color would fade over time. "So to find a lasting shade of blue was was an obsession," she says.
Maybe because of its scarcity, blue became much more than a color. It took on an almost holy quality. Brew-Hammond writes about how, in folktales in Liberia, it was explained as a gift connecting God to humans. It became about wealth and elitism.
"I also learned ... whenever there's any sort of commodity that is desired, especially by the wealthy, of course then you get the cruelty of humanity involved," says Brew-Hammond.
In India and Bangladesh, some poor farmers were tricked or forced into growing indigo. It was also part of the slave trade in Africa and in the United States.
Is that why, Brew-Hammond wonders, we sing the blues? And feel "blue" when we're sad? Do we say "true blue" because blue was so desired, that people used to peddle in cheaper, fake blues? Think of the expressions "out of the blue," "royal blue," "blue notes," for example.
"There's so many ideas attached to it," says Brew-Hammond. "Tracing those things back to some of these histories was really interesting and profound to me. They didn't just come out of nowhere. They are anchored in... historic realities that we're living with that we don't even realize."