Flowers of Camellias

Colours  vary from pure white through pale and rich pinks to red. Most shades of pink are pretty pure, but there are some salmon-orange pinks and others have a slightly mauve tint. Reds vary from a fairly matt to bright not-quite-scarlet and some of the rich crimsons can appear nearly black on the edges.

There are one or two lilac-purple varieties. Petals may also be striped or blotched with a darker or lighter shade; every flower is differently marked and some will be almost entirely either the darker or lighter shade, making it look like 2 different varieties on the same bush.

Stamens  are always yellow and make an excellent contrast, especially in the single reds. In many species and varieties they all grow forward (like toothbrush bristles); in others, especially Sasanquas and Higos, they are more open and splayed out. They may also have partly or completely converted to petals; these are called petaloid stamens.

Sports  It is not uncommon for a plant to produce a sport, ie a branch with flowers of a different colour. Sometimes, a completely new variety is produced by taking cuttings from that branch.

Some varieties are famous for producing sports. The rich-pink Elegans produced at least 6 named sports, including the pale pink sport called C.M.Wilson, which in turn produced a pure white sport which was named Shiro Chan , a Japanese name appropriately meaning White Child.

One circle of 5-8 petals and lots of stamens.

2 or more circles of petals and lots of stamens
Circle of petals and a central mass of petaloid stamens, like a carnation or anemone.
Peony-form = informal double
Rounded flower with lots of petals, often with stamens mixed among them.
Rose-form double
Lots of overlapping petals carefully laid out, opening to show stamens in the middle.
Formal double
Flat flower with lots of overlapping petals, carefully arranged, getting smaller towards the centre.