Well, we come to purple, which is a difficult colour to get right. Is it mauve? Lilac? Violet? For it isn’t quite the “purpur” of the Roman senator’s tunic stripe, if we think of the seventh chakra. For the Romans purle was Tyrain (Phoenician) and made from sea snails it is a colour closer to the reds than the blues. Think foxglove! (cf. @gertex)
Tyrian purple (Wikipedia)
Purple is a fairly modern colour to wear casually, reserved for royalty and old ladies in the Victorian era, still. It still can be a bit of a “heavy” or holy-moly colour. It is a very difficult colour to paint, because it soon drowns the picture in darkness. While a magenta room is warming and soothing, a purple room can make you feel like the walls are coming at you. 
Sarah Bernhardt in Lorenzaccio by Walter Spindler
In spiritual terms it is the final colour before the darkness; the colour of the last days of days, when all light must come from within (and no more shall your screens shine!). It means to say: eternal life or light of consciousness cannot ever be found in our desperate hopes of immortality. Cryogenics is the materialists fear of death manifest - not a realistic attempt at resurrection.
What is Cryogenics and how does it work?
Every author, artist, Oscar winner and president will be forgotten with the final implosion/explosion or whatever closing grand finale of planet Earth, one day…
In Colour Painting Therapy (in the style of Liane Collot d’Herbois) we call the colour you also find for SAHASRARA, the 1000-petal lotus crown, violet. If Indigo was a snake pit if you fell too hard and too deeply, violet is a cauldron of no return! It’s a tricky colour to master the qualities of, hence all the connotations of perfection and samadhi and nirvana and the crystalline clarity of objective, selfless observation. Would moksha/enlightenment be the ideal condition for human consciousness? Hmmm…. My guess is this pure simplicity is a bit more complex and multi-dimensional, yet. Start, I suggest, by sitting still and exploring the sounds A - U - M as you let them reverberate in your inner silence. (The Science of the Sacred Word - Being a Summarised Translation of the pranava-Vada of Gargyayana, by Bhagavan Das, comes in three volumes covering each letter separately to explore the AUM sound of perfect cosmic harmony)
kunzite pendant - great for neuralgia, against depression, self-reflection, humility and surrender to your Higher Self.
middle: cactus amethyst cluster, surrounded by crystals and amethyst prism, kunzite above, also the corner of a more robust piece, sugilite pendant inbetween.
below:kunzite pendant on charoite, sugilite pendant on kunzite
The crystals for the crown chakra are most often violet, like the ever popular amethyst or the creamy sugalite and the fragile kunzite. These crystals are often said to embody the qualities of divine love and compassion, as well as cosmic harmony. But what exactly is that all that about?... It all ties into finding the eternally Feminine, a Sophia-force, a wisdom, which is the ultimate state of a whole and happy soul. You could get there on an orange calcite or some green prehenite, why not… it’s about tuning into what you’re really made of (different specks of stardust and then summink else besides…).Holistic systems of healing, however, give you a more layered and step-by-step approach.
Don't hesitate to ask for more information on the therapeutic aspects of violet as directed by Liane Collot d'Herbois, or more details on specific crystals that took your fancy.
If you aren't ready yet to crown your healing, get ready to be ready and don't forget to breathe!
Blessings to all.
Your @suhasanasister
Amethyst with citrine and small prisms of quartz