Costus root is one of the oldest aroma-materials used in human culture - as its scent is both obvious and intriguing in the raw root itself - it is mentioned in the Old Testament already, as a precious and noble ingredient worthy of the troubling to import it from India to the ancient Near East - for ritual cult use (and the name originated in Sanskrit as well).
Extracted from a single, specific species Saussurea lappa (costus) - now renamed Dolomiaea costus - in the diverse Costus family, of over a hundred different species, Costus root essences belong to a small group of plant-origins' botanical materials with clear and loud Animalic profile - making it a real and valuable 'secret ingredient' spice. And Costus essence is not just impactful - it is intensely redolent and powerful to the point of ovewhelming and nauseating in high doses - due to its impactful core character as well as its exceptional lingering tenacity. The hydro-distilled essential oil is more radiant, 'clean' and diffusive than its Absolute, while the Absolute is a bit more earthy, slightly 'dirtier' and heavier, and even more tenacious - die to higher resin' content.
Costus is also particularly interesting because it projects itself differently at different concentrations - becoming truly elegant, ravishing indeed at lower percentages, showing a multifaceted and highly original musky-woody nuances which bring on sensual excitement, changing the character of any composition even when present at mere traces of fractions of percent, and adding not just that animalic pheromonic fascination and woody-earthy depth, but introducing a magnetic mystery vibe 'je ne sais quoi', making one guessing, 'what's that I'm smelling there at the depth?' - instead of 'in-your-face-wet-dog chewing-dirty-sock' - musty-raunchy kick at higher doses. Subtlety in the use of Costus root is really rewarding.
While buying the 100% pure essence (mine is from 'Hermitage' of Italy), I dilute it to 20% - for a subtler control of the dosing - to provide a lighter touch and prevent overtaking the composition by accidental overdosing with one drop too much.
Important aspect is that Costus root - just like Ouds and Patchouli - benefits from maturation - the graceful aging through years, losing any harsh and acrid notes that usually are present in the freshly extracted essences, smoothing out and becoming really suave - while keeping its power.
A very important aspect to be aware of - is two serious Safety issues about Costus root:
1. It is the Contamination by using other - cheaper and easier to source toxic plants - as raw material - instead of the real fragrant Costus, which was and still is annoyingly common - both intentional (by nefarious scoundrels) and unintentional (by irresponsible ignorants) - resulting in the cancer-indusing chemical (Aristolochic acid) plentifully present in the contaminated essence - at dangerous toxic levels - so Costus root essences should be sourced ONLY from the most reputed and professional sources who are well-aware of this problem and take care to monitor that critical aspect of its quality.
2. Another issue is that Costus root - both as the raw root and as the essense - inherently contains fragrant Lactones (like Costunolide) that are at the core of its captivating scent - which incidentally are strong skin sensitisizers - they make the skin very sensitive and prone to irritation - especially in sensitive individuals, which may result in severe and lingering inflammations (contact dermatitis).
For that reason - the all-powerful IFRA cartel has outlawed the real Costus root, effectively banishing it completely in 2023 for use in fragrances - instead promoting a synthetic reconstruction base called 'Costus Oliffac' - that has zero real Costus root in it and is made by IFF corporation (a member of IFRA). So you can use the real Costus essence cautiously on yourself (or a private individual client) - first testing for skin sensitivity (and in low-% dilutions), but there are no mass-produced perfumes on the market with Costus root in them, not even in traces - unless the producer is not IFRA-compliant.
I believe, practicing a cautious, prudent approach in the use of Costus essence allows it to be carefully introduced in artisan fragrances - and at around 0.1% in the final product it may be both impactful enough and safe enough - to enjoy its magic. I usually make a separate accord with it - to balance it properly with buffering materials - like Lavender, Rosewood, Magnolia leaf and Sandalwood, and then using it as a 'Spice of Elegant Intrigue' - patricularly as a nuancing companion to other Animalics (or other Animalic-mimicking plants - like Angelica root, Ambrette seeds and of course Ouds), while always conducting the sensitivity test on the client's skin prior to the blending (at very low dilution).
