Metamorphic

Metamorphic rocks are created when Igneous or Sedimentary rocks are reformed by heat and pressure.

Take a look at the Metamorphic rocks below and discover their origin story.

Gneiss

Gneiss is created when Granite or Diorite is subjected to heat and pressure, The minerals form bands instead of being randomly scattered. All of the Biotite has formed the black bands you see here. If Granite with Potassium Feldspar was turned into Gneiss you would see pink bands in the Gneiss too. Gneiss forms a large portion of the Canadian Shield.

Marble

Marble is formed when limestone crystallizes from pressure. You can often find limestone boulders in Ontario with Marble crystalization on the outside. Both will react with acid since there is plenty of the mineral Calcite within.

Quartzite

Quartzite is formed when Chert or Quartz sandstone is under heat and pressure. As the name suggests, there is lots of Quartz made up of this rock. You can know its Quartzite from the very large Quartz crystals and the lack of large quantities of other minerals. Kilarney in Ontario has lots of Quartzite. It can come in various colours such as all white or grayish pictured here.

Slate

Slate is created when Shale is under pressure. The layers are still present but it is not easily taken apart. Slate was used for blackboards and is used today for patio stones, back splashes and flooring.

Soapstone

Soapstone is created when Peridotite, Talc Shist or Serpentinite with lots of the mineral Talc is put under pressure. Because Talc is so soft, Soapstone is as well and this makes for a rock that can be shaped and formed into many shapes. It is used for carving.

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