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Inclusions that look like water lily leaves are a typical feature of peridot.
Peridot

Star sapphires are filled with elongated crystals of rutile (often
called 'silk') arranged in three directions parallel to the faces of the
hexagonal prism. When such a stone is cut in a dome shape, with its base
parallel to the basal plane of the crystal, a six-pointed star (or
sometimes a twelve-pointed one) is seen in the reflected light of the
sun or a spotlight.
Inclusions are definitively no longer considered blemishes that lower the value of gemstones. They are precious and beautiful wonders that unquestionably add value to them! The recognition and the understanding of these inclusions is a key skill to learn for all gemologists or gemstone buyers who want to know which stones they are dealing with

Furthermore, some inclusions are just beautiful in themselves: Golden needles in high luster quartz, insects trapped in Amber, fine liquids of incredible complexity in sapphire, crystals looking like star ships in rubies, cavities with tails in emeralds, or sapphires. Some gemstones rely on their inclusions for their effect, like aventurine quartz, or star sapphires. Green aventurine quartz is actually colourless quartzite, filled with tiny flakes of green fuchsite mica that lend it colour.
Rutile Needles in Rock Crystal

The insect like inclusions are a common feature of Moonstone
Needle like rutile inclusions are sometimes found in Quartz
The bright interference colours at the bottom are due to zircon crystals
Rectangular cavities with tails are sometimes found in Indian Emeralds.
Emerald Almandine Garnet Quartz Moonstone




Epigenetic: Formed after the gem was grown. Typical from this type are limonite, iron staining or oil that can fill the natural fissures of the gemstones.
Inclusions are extremely precious to the gemologist as
more synthetics and treated stones are present in the market everyday.
Learning to recognize these inclusions is essential knowledge for the
gemstone buyer as he will be better able to separate the fine natural gems
from material that is the result of human expertise in crystal growing or
heat treatment.
Gemologists classify inclusions in 3 groups:
Protogenetic: Which were formed before the gemstone host, they are always
mineralistic, typically crystals more or less corroded.
Singenetic: That formed at the same time as the host crystal. They were
imprisoned inside it during its formation or have appeared during its
cooling as rutile needles in rubies and

Diamond with Garnet
Solid inclusions may be the same gem type as the host, or different — like the garnet in this diamond.

NATURAL INCLUSIONS
Inclusions in a gemstone, viewed through a microscope or a 10x loupe, can give information about the geological environment in which the mineral was formed.
Inclusions can sometimes identify gemstones and they can prove whether the stone is natural or synthetic. Inclusions can also tell us where a gemstone comes from