It is an entry to the Rainbow contest, more info here [link]
My collection of semi-precious stones has grown a lot, and is still going to grow. ^^ It barely fit to my scanner.. and scanning them is better than photographing.
Let me show you some of the more and less known stones and tell you some interesting facts.
from up, left1. avanturine, chrysocolla, chalcedony, lepidolite, rose quartz
Chrysocolla: the more blue is contains, the higher grade it is.
Lepidolite is a form of mica.2. jade, amazonite, chalcedony, 2x amethyst, 2x lapis lazuli (lazurite)
Jades come in huge variety, from light to dark.
Amethyst seems to be the most popular stone.3. unakite, prehnite, chalcedony (blue lace agate), dumortierite, falcon's eye
Prehnite is usually apple-green colour.
Agate is a type of chalcedony.4. heliotrope (bloodstone), serpentine (snake stone), aquamarine, sodalite, kyanite, moss agate, hematite
The little dots of red on heliotrope was said to be Christ's blood that got caught on stones under his cross.
Serpentine can be used as anti-venom against snake bite.
Kyanite: long time ago, every blue stone was called kyanite.5. brown jasper, fluorite, rhyolite, quartz, ulexite, magnezite (howlite)
Fluorite is a stone with a huge colour variety - yellow, green, purple... often making stripes.
Rhyolite is of volcanic origin.
Ulexite has a peculiar optical quality, it shows whatever is behind it on its surface like a little TV - it consists of fibres which lead light, so the image can be seen only through one side, from the other sides it gives the same shiny effect like a tiger's eye.
Howlite is naturally white and sometimes is coloured blue, then it is called turquenite and is used instead of real turquoise.6. tiger's eye, yellow jasper, smoke quartz, moonstone, almandine (indian garnet), zebra marble
There are 3 types of tiger's eye - red, blue and yellow. Blue is called falcon's and red is called bull's (but only in my country, what a shame.)7. japser (not sure which type), yellow calcite, citrine, agate, red tiger's eye, mahogany obsidian
Jaspers are opaque stones with an amazing variety of patterns. There is red, yellow, brown, leopardskin, picture, brecciated, dalmatine, picasso, kalahari, oceanic, jungle jasper... some are very hard to categorize. Also heliotrope and unakite belong to jaspers.
Citrine is usually artificially made from amethyst, real citrine is paler and hard to find.8. leopardskin jasper, chiastolite (cross stone), grey agate, rutilated quartz, carnelian, red jasper (probably brecciated)
Chiastolite is a type of andalusite, it always crystallizes in the typical structure. If cut properly, a nice regular cross can be seen.
Quartz with needles of rutile inside is also called Venus's hair (in my country).
Carnelian can be with stripes.
Hope you enjoyed this little lesson of mineralogy.