Ask any person in India what is the colour of renunciation and they will invariably answer ‘saffron’.
Saffron is a colour signifying sacrifice, piety and all things sacred. It is a colour that is worn by sannyasis of every sampradaya – Hindus wear it, Buddhists wear it and Sikhs wear it. It is also prominently included in the tricolour Indian flag, indicating how the leaders of the country must be indifferent to material gain and work diligently for the benefit of others.
But is saffron really the colour of renunciation?
The word ‘saffron’ comes from the Old French safran, based on the Arabic word za‛faran. The saffron plant is known as the Saffron Crocus and each flower has three red stigmas that are plucked and dried. These dried stigmas are used as a spice in cooking, for perfumes and for medical preparations. Saffron was also used as a colouring agent for almost 3000 years throughout Central Asia.
However, cloth that is dyed with saffron becomes bright yellow, and yellow is not the colour of the garments worn by sannyasis. Thus, saffron is actually a misnomer for the colour of renunciates.

So what colour did sannyasis wear in Vedic times? What was the name of that colour and how was it made?
If we look in the Vedic dharma-shastras we find an abundance of references that refer to the colour of the sannyasa-ashrama.
stutva hamsam suktairmano vaishnava-paurushaih
mundah shikhi va kashayi patri dandi grihad-vrajet
After chanting the Vishnu-sukta and Purusha-sukta in the mind, let him depart from home dressed in kashaya, carrying a bowl and a staff, and with his head completely shaved or wearing a shikha (Kratu)
sarvarambhan-utsrjya tridanda-kundika pakshma-pavitra-prayojanapekshi mundah kashaya-vasa bhaiksha-vrittir
Abandoning all household rituals, he relies upon the use of a tridanda, a water pot, a sacred thread, a water strainer, shaves his head, wears cloth the colour of kashaya and subsists on begging. (Sankhayana and Likhita)
kashaya mundi tridanda kamandalu patra pavitra paduka-asana kantha matra
The articles consist of kashaya cloth, a shaven head, a tridanda, a water pot, a bowl, a water strainer, a pair of shoes, a seat and a shawl. (Angiras)
tatra kutichaka nama putradibhih kutim karayitva kama-krodha-lobha-moha-mada-matsaryadin-parityaja vidhivat-sannyasam kritva tridanda jala-pavitra kashaya-vastra-dharanih
Those sannyasis known as kuticaka are those who request their sons to build them a cottage; they give up lust, anger greed, illusion, madness and envy etc. They renounce the world thus and carry a tridanda, a water-strainer and wear cloth dyed the colour of kashaya. (Parasara)
bahudaka-nama tridanda kamandalu pakshma-pavitra shikya kashaya-vastra dharino
The sannyasis known as bahudakas carry a tridanda, a kamandalu, a water-strainer made of fine cotton, a shoulder bag and they wear kashaya cloth. (Parasara)
tridandam jala-pavitram shikyam patram kaupinam kashaya-vastram agni-samnidhau samsadhyanagninamagnyut-padanam ekagni-vidya neneti
He should place the tridanda, water-strainer shoulder bag, bowl and kashaya cloth in front of the sacred fire. A man without a sacred fire should set one up. (Katyayana)
kashayam eva karpasam vasam kantham ca dharayet
valkalam vajinam vapi kausham shanamayam tu va
The sannyasi should wear a shawl, kashaya cloth, tree-bark, deerskin, kusha-grass of hemp. (Likhita)

We also find references in the Upanishads:

atha bahudaka nama tridanda kamandalu
 shikha yajnopavita kashaya-vastra dharino
The bahudaka sannyasis carry a tridanda, a kamandalu, they maintain their shikha and sacred thread and kashaya cloth. (Bhikshukopnisad 3)
kashaya-vasah satatam dhyana-yoga-parayanah
gramante vriksha-mule va vase devalaye 'pi va

Wearing kashaya cloth, and devoted to yoga and meditation, the sannyasi may take shelter at the outskirts of a village, the shade of a tree or even in a temple. (Narada-Parivrajaka Upanishad 5.34)

The Puranas also state:

shikhi yajnopaviti syat tridandi sa-kamanduluh
sa pavitras ca kashayi gayatrin ca japet sada
A tridandi-sannyasi keeps his shikha as well as his sacred thread after renunciation, He also carries a kamandalu. He wears cloth, the colour of kashaya and remaining fixed in purity, he chants the gayatri mantra and always chants japa. (Skanda Purana, Suta Samhita)

In Sanskrit the word used for the colour of a sannyasi’s robe is kashaya. According to various Sanskrit dictionaries, kashaya is a red-brown hue – very different to the pink, peach and orange dyes that we see Vaishnavas wearing nowadays. The Sri Vaishnava acharya, Yadava Prakasha, in his famous work Yati-dharma Samucchaya, explains how the colour kashaya is produced:
yadyapi kashayam ityavisesheshenoktam tathapi gairikakhya dhatuna ratktam kartavyam.
Even though the word kashaya is used (in the Dharma-shastras) without further detail, one should dye the cloth with the red mineral known as gairika. (Yati-dharma Samucchaya 8.64)
The Dattatreya-samhita also explains:
mokshashrame smritam vastram raktam gairika-dhatuna
The smrti prescribes a cloth dyed with the mineral known as gairika for those who are in the order of life devoted to liberation.
Gairika (Hindi: geru) is known in English as Red Ochre or Iron Oxide (Fe203). It is a natural non-toxic mineral pigment found with other iron-titanium oxide minerals
We find in the works of the Vaishnava acaryas that gairika is used to decorate Sri Krsna. One of the names of Krsna found in the Radha-Krsna Sahasranama Stotram is Gairika-chitrita-vapu – One whose body is decorated with designs made from gairika. Srila Vishvanatha Chakravarti Thakura writes in his Vraja-riti-chintamani:
yad-dhavato gairika-hinguladya
manahshilakhya haritala mukhyah
ati-priyah shyama-sharira-shobha
lobhaya kurvanti vidhu-priyanam
The minerals such as gairika, kum-kum, yellow arsenic and red-arsenic found on Govardhana Hill are all very dear to Sri Shyamasundara as they decorate His body for the pleasure of His beloved Gopis. (VRC. 3.5)
The Vaishnava poet Govinda Dasa also sings:
girika gairika goraja gorocana
gandha garabhita vesha
Krishna is decorated with gairika, gorocana, anointed with sweet perfumes and dressed in graceful garments.

Gairika has been used by various cultures throughout the world – 

* Gairika has been used for centuries in Ayurvedic medicine for enhancing red blood cells and curing anemia.
* Artists in Ellora and Ajanta used gairika as paint.
* Neanderthals used Gairika in death-rites 200,000 years ago.
* Cro-Magnons used gairika in wall paintings in Southern Europe 32,000 years ago.
*The Picts and Celts used gairika to paint themselves before going into war.
* In Germania (Ancient Germany), gairika was used to redden carved runes in order to instill life into them.
*The North American Indians applied gairika to their bodies – hence the first European settlers referred to them as ‘Red Indians’.
* Women of the Himba tribe in Nambia use gairika to decorate their bodies and hair.
* In Chinese medicine gairika was used to calm the liver and cool the blood.
* The Maoris of New Zealand used gairika extensively as war paint, for painting their canoes and as an insect propellant.
*In Ancient Egypt gairika was used as rouge and lip gloss for women.
*In the ancient Mediterranean world, gairika was the most commonly used material for painting walls with.
*Medieval and Renaissance frescoes such as the one painted by Giorgio Vasari on the walls of the Hall of 500 in Florence were made mainly by earth pigments, such as gairika.

From this we can see that gairika was one of the earliest natural pigments used by mankind.
Today, most textile manufacturers use chemical dyes to color their products. This is because it is much easier, faster and the range of colours one can create is much broader. Synthetic dyes also last longer than natural dye. However, the downside is that many chemical dyes are harmful to the environment and poisonous. Prominent cloth dyes such as Dioxin, Azo III A1 and A2 and Formaldehyde can be absorbed through the skin and act as carcinogens.
When Srila Bhaktisiddhanta Sarasvati Thakura inaugurated his preaching mission, Sri Gaudiya Matha, his sannyasis and brahmacharis used gairika to dye their cloth. Nowadays however, gairika has gone out of vogue and synthetic dyes of all different shades and colours have become the norm for renunciates of all Vaishnava societies.
Renunciation means simplicity and what could be simpler than using natural minerals provided by Mother Nature herself as opposed to artificial chemicals?