Shades & Tints Of Blue

"Blue", the hue, is the wavelength of light that most stimulates the blue sensor in the human eye. It is one of the three additive primaries and is present in as a single pixel in all computer display devices. It is one of the most famous colours of all and is the most popular colour among humans. It is commonly associated with the sky, the sea, ice, cold, and sometimes with sadness.

Interestingly, most of the colours that people think of as "blue" are not of this hue at all, but between true Blue and Green. Examples include the sky, the sea, robin's eggs, duck eggs, turquoise and "blue" spruce. Examples of true Blue hue are more limited with just a few minerals, cut gem stones and synthetic chemicals to cover the darker shades. Tints of true Blue suffer badly from the Abney effect meaning that Forget-Me-Not and Cornflower appear to be of Violet hue, but they are not.

It is amazing that such a famous colour should be so rare in nature and the lack of secondary exemplars here demonstrates that beautifully as no other hue is so hard to find examples of! Go figure...

There were a lack good pigments and dyes for Blue from the beginning, with the only really clean and lightfast blues being Lapus Lazuli which was very expensive and Egyptian Blue whose secret of manufacture was lost. Nonetheless there were cheap, temporary options with dirty dyes, so it has always been well represented in clothing if not so much in painting. Such pigments include: Indigo from the plant Indigofera tinctoria, Smalt from powdered cobalt glass, and Woad which was obtained from the plant Isatis tinctoria.

Today there are other spectacular bright and clean blues available such as: Pthalo Blue and synthetic Ultramarine Blue.

Forget-Me-Not	Forget-Me-Not	Blue Plumbago
HSB 235°, 30%, 100% RGB 179, 185, 255
"Forget-Me-Not" is the colour of ...	Forget-Me-Nots are flowering plants of the genus Myosotis. There are approx 200 species in the genus of varying flower colour. This is Myosotis scorpioides or the "True Forget-Me-Not".	Plumbago is a genus of flowering plants comprising more than 10 species of varying colours. This is Plumbago auriculata.

Cornflower	Cornflower	Bluebell
HSB 235°, 48%, 100% RGB 133, 143, 255
"Cornflower" is the colour of a number of flowers, not only these but also including love creeper and blue pin cushion.	Cornflower, Centaurea cyanus, is a small flowering plant native to Europe. They do vary a little in colour but by_and_large this is what they look like.	The common bluebell, Hyacinthoides non-scripta, is a bulbous perennial plant particularly associated with ancient woodland where it may dominate the understorey to produce carpets of light blue flowers.

Light Blue	Sapphire	Blue Tinsel Lily
HSB 240°, 65%, 100% RGB 89, 89, 255
"Light Blue" is the colour of many cut sapphires in good light and a few flowers.	Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminium oxide (Al₂O₃) with trace imputies of iron or titanium. A good specimen of cut sapphire is true blue. Light blue is the mid tone here. Blue is the deeper tone. Sappires can vary in tone so some may be darker than this.	Blue Tinsel Lily, Calectasia intermedia, is a rhizomatous perennial herb naturally occuring in a pocket of south eastern Australia.

Blue	Lapis Lazuli	Missing
HSB 240°, 100%, 100% RGB 0, 0, 255
"Ultra Marine" is the colour of Lapis Lazuli.	Lapis Lazuli is a rock which contains lazurite, a mineral with the formula (Na,Ca)₈[(S,Cl,SO₄,OH)₂\|(Al₆Si₆O₂₄)]. This has an intense blue colour due to the presence of S^-₃ ions. Its colour may vary toward cyan due to impurities. It may be ground to produce natural Ultramarine pigment which was the only blue available in the middle ages. It was very expensive so it was only used by the Church and the rich until a synthetic ultramarine was invented in 1826. It was often used for the robes of the Virgin Mary.	If you find another natural object of the colour swatch on the left please email me.

Dark Blue	Scottish Football Team	Missing
HSB 240°, 100%, 48% RGB 0, 0, 122
Dark blue is NOT "Navy Blue", which is the colour of various uniforms, although, interestingly, not most naval uniforms! Originally all Navy uniforms were dyed with indigo, so the old versions of this colour and modern imitations are actually Prussian Blue or Cobalt Blue. Dark true blue is much rarer as it was not possible to dye this colour until recently.	It has taken a while but some organisations have taken up this modern hue, which is pure dark blue. Here is an example worn by the Scottish National Football Team.	If you find another natural object of the colour swatch on the left please email me.