Courtesy of: http://www.nhm.ac.uk/
Frankincense – sometimes called olibanum – is a gum-resin. Historically, it is one of the most valuable substances in the world and the source of a major trade empire.
The first records of frankincense date from around 1500 BC, when Queen Hatshepsut of Egypt sent an expedition south into Africa to bring back frankincense trees. The event is commemorated on the walls of the temple near Luxor where 2 of the trees were planted. However, frankincense was known to the people of Arabia and the Horn of Africa long before this.
For centuries the precise origin of frankincense and the plants that produce it were shrouded in myth and mystery. People harvesting the gum-resin discouraged outsiders, and wild tales of guardian monsters were common.
In 1905, the Officiating Reporter on Economic Products to the Government of India sent out an appeal for information and specimens, admitting that the authorities were “remarkably ignorant of the origin of frankincense” and knew “no more than a third of its story”.
The first scientific collections of Boswellia sacra were made in 1846 but the best trees (in Oman) were not adequately described until the 1930s. Even in the 1980s researchers did not have enough specimens for study.
Frankincense is obtained by making a series of cuts in the bark of the trunk and branches of the tree, from which the gum-resin exudes. The cuts are often very rough but if limited, the trees suffer no permanent damage.
There are 2 cutting seasons for frankincense: the autumn cutting yields highly aromatic white gum while the spring cutting yields an inferior red-brown gum.
Although frankincense is less important than it once was, the trees still form an important part of local economies and trade continues to supply perfumers.
Traditionally, frankincense had both sacred and more mundane uses, including:
as incense – used for all important religious rituals and occasions, and so complete was this link, frankincense gave rise to what was known as the ‘odour of sanctity’ associated with sainthood
as a medicine – used internally and externally to combat almost every disease and condition – both physical and mental – in humans and animals by physicians from Rome and ancient Greece to the Middle East, India and China
as a cosmetic and skin care product – powdered, low-grade frankincense was used for this purpose
in warfare – it was mixed with pitch, sulphur and other ingredients to produce an almost inextinguishable fire to burn enemy strongholds and was also fed to war elephants to enrage them before battle
In the ancient world, gums were a highly valued commodity and it was no accident that frankincense (along with gold and another gum-resin, myrrh) was one of the gifts brought by the wise men to Jesus. This was the period when the frankincense trade was at its peak and the gum was deemed as valuable as gold. There were, and still are, numerous grades of frankincense which depend on:
- the species
- the area of origin
- the growing conditions
- the harvesting season
The different grades are given a bewildering variety of local names.
Frankincense was known to the Sumerians (around 3500 BC) and over the centuries a thriving trade developed between producing areas and markets as far online casino’s away as Europe, India and China. At its height, the trade supplied 3,000 tons to the Roman Empire alone. Twice a year, camel trains carried high value cargoes along the Incense Road from areas including Oman and Yemen via cities such as Damascus and ports such as Alexandria and Gazza to be sold in Middle Eastern and Mediterranean markets and beyond. The trade was extremely lucrative and attracted high taxes from towns along the routes.
Frankincense is produced by several species of the genus Boswellia. All are trees or shrubs.
The finest and most aromatic gum-resin comes from Boswellia sacra (also known as Boswellia thruifera), a small tree up to 5m high with 1 or several trunks covered with peeling, papery bark.
The leaves are crowded towards the tips of the thick twigs. Each leaf is divided into 6–8 pairs of oblong leaflets increasing in size towards the top of the leaf which is tipped by a single, largest leaflet. The leaflets all have distinctive, wavy margins and are hairy, very densely so on the underside.
The flowers are also borne at the tips of the twigs. They are loosely grouped into long, slender spikes, have five white petals and a central disc which turns from yellow to red or black as the fruit develops.
The fruit is a capsule with 3–5 longitudinal wings and opens by means of 3–5 valves, each releasing a single seed.
The genus Boswellia is named for John Boswell, uncle of James, the biographer of Samuel Johnson.
There has been, and remains, considerable confusion over the number and delimitation of the species of Boswellia. This has been compounded by:
- a lack of good specimens for study
- the wide array of common names, mostly relating to the gums produced rather than the trees themselves
- the considerable morphological variation found in this genus
Boswellia sacra is restricted to the southern Arabian Peninsula and the north-east coast of Somalia. Although it tolerates a range of conditions, it prefers arid, cool areas.
In Dhofar and Yemen – the most famous and productive areas – the trees thrive in the rain shadow of the monsoon mountains.
Trees growing in damp conditions produce less, and lower quality, gum-resin.
Frankincense is a plant product referred to as a gum-resin. It is a mixture of gum, resin and volatile oil which provides the perfume of such substances and comes in different forms, depending on the species from which it is obtained.
The best quality gum-resin is initially a rather elastic substance which dries hard. It is oily and highly inflammable. Inferior forms are less resilient and break down into a sticky liquid.
The gum-resin is strongly scented, described as woody and balsamic, honeyed but not cloying.
The bark of frankincense trees is rich in resin ducts. When pieces of the outer bark are removed, the resin bleeds out.
In the case of Boswellia sacra, this gum-resin hardens into white blobs called pearls or beads, which are harvested by hand. These may be sold as they are or softened and moulded into a variety of shapes.