Sapphire:  Sapphire is from the corundum group of minerals. Its colours range from yellow, orange, pink, green, purple, to blue. All reds are designated as Rubies. There is no definite demarcation between sapphires and rubies, so light reds, pinks or violets are termed sapphires The most desirable and valuable colours are the cornflower blues.

Aquamarine:  Aquamarine part of the beryl family of gems and therefore closely related to Emerald. The darker blue green colour is thought to be the more desirable. The preferred cut is emerald or scissor cut, along with long oval shapes. Can sometimes be mistaken with Topaz.

Tourmaline: Tourmaline is a gem found in multi-colours. It’s one of those gems designated according to colour; in this case it’s called Indicolite, available in every shade of blue. Most have a hint of green, and pure blues are expensive, generally being collectors’ stones. They are sometimes referred to as Paraiba Tourmalines. Recently, new sources have been discovered in Africa.

Starlite:  Starlite is a heat treated zircon. Often confused with Cubic zirconia (synthetic diamond lookalike) Natural zircons do occur colourless and were a popular substitute for a diamonds, this is where the confusion has arisen. Zircons also occur in yellow and reds (Hyacinth). Green zircons are rare, often sought after by collectors.

Tanzanite: Tanzanite was originally known as blue Zoisite, but was rebranded in the 60s, by New York Jewellery company Tiffany & Co. (because the word Zoisite, was said to sound a little too like the word Suicide) The new name quickly caught on in the trade. Tanzanite is characterized by its blue to purple colour

Iolite:   Iolite comes from the Greek word ‘ion’ meaning violet. Iolite is also referred to as cordierite and dichroite. Thin slivers of it were used by the Vikings for navigation. They used its polarising qualities to help mark the position of the sun on their various conquests across the seas. The richer blues are more desirable. Iolite is inexpensive and readily available.

Amethyst:    They belong to the quartz group and are classed as semi-precious. Amethyst is regarded as the most valuble of the quartz Family .They are often confused with beryl, Kunzite and topaz.. Some people believe that amethysts have supernatural powers regarding health and wellbeing.