Sandalwood is a class of woods from trees in the genus Santalum. The woods are heavy, yellow, and fine-grained, and, unlike many other aromatic woods, they retain their fragrance for decades. Sandalwood oil is extracted from the woods. Sandalwood is often cited as one of the most expensive woods in the world. Both the wood and the oil produce a distinctive fragrance that has been highly valued for centuries. Consequently, some species of these slow-growing trees have suffered over-harvesting in the past.
Nomenclature The nomenclature and the taxonomy of the genus are derived from this species' historical and widespread use. Etymologically it is ultimately derived from Sanskrit Chandana (čandana), meaning "wood for burning incense" and related to candrah, "shining, glowing" and the Latin , to shine or glow. It arrived in English via Late Greek, Medieval Latin and Old French in the 14th or 15th century.
True sandalwoods
Sandalwoods are medium-sized hemiparasitic trees, and part of the same botanical family as European mistletoe. True sandalwoods are native to Insular Southeast Asia, Melanesia, Australia, and the Pacific Islands. The main cultivated species, Santalum album, were introduced in ancient times into mainland Asia by Austronesian traders and have since naturalized in South Asia, Mainland Southeast Asia, southeastern China, and Taiwan. The main distribution of both wild and introduced sandalwood trees are in the drier tropical regions of India and the Indonesian islands of Timor and Sumba.
S. album spread to other regions through the Austronesian maritime trade network, the incense trade route, and the Maritime Silk Road, until the sixteenth century CE. The sandalwood produced in peninsular India and the Malay Archipelago supported most consumption in East Asia and West Asia during the time of the incense trade route before the commercialization of Australian sandalwood (Santalum spicatum) in sandalwood plantations in Australia and China, although sandalwood album (Santalum album) is still considered to have the best and original quality in terms of religion and alternative medicine. Santalum spicatum is marketed as the notable member of this group today by merchants because of its stable sources; others in the genus also have fragrant wood. S. album is a threatened species native to dry tropical regions of Indonesia (Java and the Lesser Sunda Islands), the Philippines, and Western Australia. It was one of the plants exploited by Austronesian arboriculture and it was introduced by Austronesian sailors to Mainland Southeast Asia, South Asia and East Asia, during the ancient spice trade, becoming naturalized in South India by at least 1300 BCE. In India, the principal sandal tracts are most parts of Karnataka and adjoining districts of Maharashtra, Tamil Nadu, Kerala and Andhra Pradesh.Kumar, A. N. Arun, et al. "Sandalwood: History, Uses, Present Status and the Future." Current Science, vol. 103, no. 12, 2012, pp. 1408–16. JSTOR, http://www.jstor.org/stable/24089347. The governments steward the land and regulate the harvest of sandalwood trees in India, Pakistan, and Nepal though many trees are illegally cut down. Sandalwood oil prices had risen to per liter by 2017. S. ellipticum, S. freycinetianum, and S. paniculatum, the Hawaiian sandalwood (iliahi), were also used and considered high quality. These three species were exploited between 1790 and 1825 before the supply of trees ran out (a fourth species, S. haleakalae, occurs only in subalpine areas and was never exported). Although S. freycinetianum and S. paniculatum are relatively common today, they have not regained their former abundance or size, and S. ellipticum remains rare.Wagner, W. L., D. R. Herbst, and S. H. Sohmer (1990). Manual of the Flowering Plants of Hawaii. Honolulu: University of Hawaii Press.Rock, J. F. (1913). The Indigenous Trees of the Hawaiian Islands. Honolulu. S. yasi, a sandalwood from Fiji and Tonga. S. spicatum is used by aromatherapists and perfumers. The oil concentration differs considerably from other Santalum species. In the 1840s, sandalwood was Western Australia's biggest export earner. Oil was distilled for the first time in 1875, and by the turn of the 20th century, production of Australian sandalwood oil was intermittent. However, in the late 1990s, Western Australian sandalwood oil enjoyed a revival and by 2009 had peaked at more than per year – much of which went to the fragrance industries in Europe. Although overall production has decreased, by 2011, a significant percentage of its production was heading to the chewing tobacco industry in India alongside Indian sandalwood – the chewing tobacco market being the largest market for both oils in 2012. Other species: Commercially, various other species, not belonging to Santalum species, are also used as "sandalwood." Unrelated plants Various unrelated plants with scented wood and also referred to as "sandalwood," but are not in the true sandalwood genus: Adenanthera pavonina – sandalwood tree, red or false red sandalwood Baphia nitida – camwood, also known as African sandalwood Eremophila mitchellii – sandalwood; false sandalwood (also sandalbox) Myoporum platycarpum – sandalwood; false sandalwood Myoporum sandwicense – bastard sandalwood, false sandalwood Osyris lanceolata – African sandalwood Osyris tenuifolia – east African sandalwood Pterocarpus santalinus – false red sandalwood growing in southern Indian regions
Production
Producing commercially valuable sandalwood with high levels of fragrance oils requires Indian sandalwood (S. album) trees to be a minimum of 15 years old – the yield, quality and volume are yet to be clearly understood. Yield of oil tends to vary depending on the age and location of the tree; usually, the older trees yield the highest oil content and quality. India continues to produce a superior quality of Santalum Album, with FP Aromatics being the largest exporter. Australia is the largest producer of S. album, with the majority grown around Kununurra, in the far north of Western Australia by Quintis (formerly Tropical Forestry Services) – which in 2017 controlled around 80% of the world's supply of Indian sandalwood – and the Santanol Group. India used to be the world's biggest producer, but it has been overtaken by Australia in the 21st century. Over-exploitation is partly to blame for the decline. However, ethical plantations in India are on the rise, and India is expected to increase its supply manyfold by 2030, owing to favourable weather conditions and competitive pricing.
Australian sandalwood (S. spicatum) is grown in commercial plantations throughout the wheatbelt of Western Australia, where it has been an important part of the economy since colonial times. Western Australia has the largest plantation resource in the world.
Sandalwood is expensive compared to other types of woods. To maximize profit, sandalwood is harvested by removing the entire tree instead of felling at the trunk near ground level. This way wood from the stump and root, which possesses high levels of sandalwood oil, can also be processed and sold.
Australian sandalwood is mostly harvested and sold in log form, graded for heartwood content. The species is unique in that the white sapwood does not require removal before distilling the oil. The logs are either processed to distill the essential oil, or made into powders for making incense. Indian sandalwood, used mainly for oil extraction, does require removal of the sapwood prior to distillation. , Australian sandalwood oil sold for around per , while Indian sandalwood oil, due to its higher alpha-santalol content, is priced at about per kg.
Sandalwood is often cited as one of the most expensive woods in the world, along with African blackwood, pink ivory, agarwood and ebony.
Sandalwood has historically been an important tree in the development of the political economy of the Pacific. Prior to colonization in the region, the sandalwood tree was a marker of status, rank and beauty. It then became an important part of the Pacific trade during the colonial period, as it was one of the few resources the West was able to successfully trade with Chinese merchants. This western trade began to put pressure on the production of sandalwood in the region.Evans, Mike. "Property, propriety, and ecology in contemporary Tonga." Human Organization, vol. 66, no. 1, 2007, pp. 22–27, https://doi.org/10.17730/humo.66.1.h65w4867x5x0j101.
Tonga, a Polynesian kingdom in the Oceania region, saw a collapse of its sandalwood tree population (locally known as ʻahi) due to the disruption of fahu, the hierarchical kinship-based social system which traditionally governed ʻahi harvest. When, in the early 1980s, a Chinese merchant willing to pay high prices arrived at the island of Haʻano, lower-ranking family members began to harvest the trees without permission, encouraging many farmers to harvest their trees defensively, leading to overharvest. Nearly all of the sandalwood resources on the island were depleted over the span of two years. Anthropologist Mike Evans concluded, "whatever the short-term ecological benefits of enforcing privatized land tenure, because private property not only fragments social ties by allowing an individual to deny others, it has the potential to fragment the regional ecology as well."Evans, Mike. "Property, propriety, and ecology in contemporary Tonga." Human Organization, vol. 66, no. 1, 2007, pp. 22–27, https://doi.org/10.17730/humo.66.1.h65w4867x5x0j101.
Uses
Fragrance
Sandalwood oil has a distinctive soft, warm, smooth, creamy, and milky precious-wood scent. Its quality and scent profile is greatly influenced by the age of the tree, location and the skill of the distiller. It imparts a long-lasting, woody base to perfumes from the oriental, woody, fougère, and chypre families, as well as a fixative to floral and citrus fragrances. When used in smaller proportions in a perfume, it acts as a fixative, enhancing the longevity of other, more volatile, materials in the composite. Sandalwood is also a key ingredient in the "floriental" (floral-ambery) fragrance family – when combined with white florals such as jasmine, ylang ylang, gardenia, plumeria, orange blossom, tuberose, lily of the valley, etc. Its also acts as a versatile base that blends well with other woody scents like patchouli and cedar.
Sandalwood oil in India is widely used in the cosmetic industry. The main source of true sandalwood, S. album, is a protected species, and demand for it cannot be met. Many species of plants are traded as "sandalwood". The genus Santalum has more than 19 species. Traders often accept oil from closely related species, as well as from unrelated plants such as West Indian sandalwood (Amyris balsamifera) in the family Rutaceae or bastard sandalwood (Myoporum sandwicense, Myoporaceae). However, most woods from these alternative sources lose their aroma within a few months or years.
Isobornyl cyclohexanol is a synthetic fragrance chemical produced as an alternative to the natural product.
Sandalwood's main components are the two isomers of santalol (about 75%). It is used in aromatherapy, in scented candles and to prepare soaps.
Idols/sculptures
Sandalwood lends itself well to carving and has thus, traditionally, been a wood of choice for statues and sculptures of Hindu gods.
Technology Due to its low fluorescence and optimal refractive index, sandalwood oil is often employed as an immersion oil within ultraviolet and fluorescence microscopy.
Food Aboriginal Australians eat the seed kernels, nuts, and fruit of local sandalwoods, such as the quandong (S. acuminatum).