Shampoo did not always come in bottles from the cosmetics counter. Three generations ago it literally grew on trees.
The tree can be found across the Middle East and its valuable properties have been known since ancient times. References to it occur among all the Ibrahim faiths; indeed, its scientific name, Zizphus Spina Christ, is a reference to the belief among some Christians that its thorns were used to crown Jesus before his crucifixion.
Al Sidr trees are also mentioned in the Quran, as one of the plants of Paradise. Its many earthly uses include disinfecting wounds, healing skin diseases and as an anti-inflammatory.
The fruit, leaves, roots and bark are used for various treatments, while in Yemen, Al Sidr honey is the most prized.
Creating a shampoo and conditioner involves nothing more than drying the leaves and then grinding them to a powder, which is then mixed with water to make a thick paste. Powdered Al Sidr can still be purchased in herbal shops today and forms the basic ingredient of Oman's Sidr range of herbal shampoos.
"The last generation that I think used Al Sidr leaves was my great-grandmother's," says Hamda Al Bu Falah, a student from the New York University's oral Al Hemyan history project.
"My mother, I think, saw her use it maybe once. It would have been used as shampoo or body wash. The story goes that they used to pick the leaves, grind them and mix them with water when it becomes a sort of soap. I guess it was really popular because you can find the tree anywhere in the United Arab Emirates.
"We have so much today compared with a few generations back. Al Sidr leaves make me look at what we have right now and how far we have come."
This object is the result of a collaboration with students from New York University's Al Hemyan project, which is dedicated to creating a digital archive by translating elements of cultural heritage into digital projects, public exhibits and art