Mini Me Geology Blog » earth science

Sedimentary Rocks

tracyb — Fri, 26 Feb 2010 15:51:07 +0000

Sedimentary rocks are formed when sand, small pieces of rock, or mud are deposited as layers of sediment. These layers of sediment are pressed together over a long period of time and form a sedimentary rock from the pressure and cementation process. Sedimentary rocks are unique because they can be formed from any other rocks type: igneous, metamorphic and even other sedimentary rocks. Rocks are broken down by wind and water and the pieces are transported to oceans and lakes by rivers and smaller streams. The rock pieces are deposited in the lakes and oceans in the layers which later become a sedimentary rock.

Sedimentary rocks are unique because they are the only types of rocks that can contain fossils of sea shells and animals. Fossils form when the soft parts of plants and animals decay and leave the hard parts (such as bones) behind. The hard parts that are left are then covered with layers of sediment. When the sediment becomes a rock, the hard parts are preserved in the rock as a fossil.

Read more about geology in the Dig Into Geology section of our website.

Staurolite Twins

tracyb — Fri, 05 Feb 2010 15:42:16 +0000

Staurolite is a silicate mineral which occurs in metamorphic rocks and is often found with the minerals kyanite and garnet. Staurolite is a 7 to 7.5 on the Mohs Hardness Scale which has a range from 1 (softest) to 10 (hardest), has a glassy to resinous luster and a colorless streak. Prismatic crystals of staurolite are common and often found twinned.

Twinned crystals of staurolite have been found in both a Greek cross with 90 degrees between the crystals and a St. Andrew’s cross with 60 degrees between the crystals. Because of the unique look of the twinned crystals, they are often used for jewelry. Beautiful specimens of staurolite can be found in Madagascar, Switzerland, United State, France and Mexico.

We carry some great specimens of staurolite twins which make a great addition to any collection. Get your samples of staurolite today!

Learn about Rocks made from Volcanoes!

tracyb — Fri, 11 Dec 2009 20:00:21 +0000

Discover some of the Earth’s most magnificent rocks in this Igneous Rock collection. Fifteen amazing samples will give you a sneak peek into both intrusive and extrusive rocks. Each rock comes with an identification card which includes a photo and fun rock facts. Try to identify each rock using the hand magnifier and information cards. If you need a hint, the name of each rock is beneath the foam padding. If you need help using the hand magnifier or identifying the rocks, check out the Dig Into Science section of our website for tips on how to use your new Igneous Rock kit.

Each kit includes:

• 15 Large Igneous Rock Samples: anorthosite, basalt, carbonatite, diorite, gabbro, granite, monzonite, obsidian, pegmatite, peridotite, pumice, rhyolite, syenite, trachyte, and volcanic breccia

• Hand Magnifier

• Identification Card for each rock

• Sturdy compartment box with snug latches for secure and organized storage

View this short video for details on our My Rockin’ Collection kits:

Samples obtained worldwide.

All other components made in the USA.

Assembled in the USA.

Safety Warnings

WARNING: CHOKING HAZARD Small Parts. Not for children under 3 years.

May have sharp edges.

The neatest rocks you probably don’t know much about

tracyb — Sat, 05 Dec 2009 14:34:30 +0000

I love metamorphic rocks. To think that each of these rocks once was a different rock and just because of some really high heat and squeezing, they became something new is really cool! Here are some details on our My Rockin’ Collection Metamorphic Rocks kit. I think you’ll agree that these rocks are cool. These kits are great for kids and adults.

You will love the variety of colors and textures in this Metamorphic Rock collection. Each of 10 rocks comes with an identification card which includes a photo and fun rock facts. Try to identify each rock using the hand magnifier and information cards. If you need a hint, the name of each rock is beneath the foam padding. If you need help using the hand magnifier or identifying the rocks, check out the “Dig Into Science” section of our website for tips on how to use your new Metamorphic Rock kit.

Each kit includes:

10 Large Metamorphic Rock Samples: amphibolite, anthracite coal, gneiss, hornfels, marble, phyllite, quartzite, mica schist, garnet schist, and slate
Hand Magnifier
Identification Card for each rock
Sturdy compartment box with snug latches for secure and organized storage

To see these rock kits in action, check out our video.

Safety Warnings
WARNING: CHOKING HAZARD Small Parts. Not for children under 3 years.

Conglomerate Sedimentary Rock Q&A

tracyb — Thu, 03 Dec 2009 19:54:18 +0000

Here is another great question we received through our Ask-a-Geologist email.

Question: What grains are in conglomerate rocks?

Answer: Conglomerate rocks are made up of many different types of grains from sand to various types of rocks.

Learn more about conglomerate with our individual samples, My Rockin Collection Sedimentary Rock kit or our Sedimentary Sleuthing Rock Detectives kit.

Today we are Sedimentary Sleuthing!

tracyb — Tue, 03 Nov 2009 21:22:47 +0000

Teach your children about sedimentary rocks with this cool Sedimentary Sleuthing kit. Your kit comes complete with six cool sedimentary rock samples: lignite coal, sedimentary breccia, conglomerate, fossiliferous limestone, yellow sandstone and shale.

Also included in the kit is a hand magnifier and a CD with 30 pages of rock information, sample identification activities, puzzles, coloring pages, and experiments. Adult supervision is required for some of the experiments.

Other fun activities on the CD include creating your own adventure story, making a personal geologist’s field notebook and your very own rock collection box!

The CD requires free Adobe Reader 9.0 which can be downloaded at www.adobe.com. This software is easy to download and use so please use version 9.0 which makes the CD very fun to view! Mini CDs fit in center of tray disk drives. The Mini CD in the kit may not play in slot drives without an adapter. Consult computer manufacturer’s recommendations before inserting the mini CD into a slot drive.

Take 25% off Your Orders This Weekend!

tracyb — Fri, 25 Sep 2009 17:02:48 +0000

This weekend only!

Take 25% Off your entire order

Use Coupon Code: ROCK25

Shop for rock kits for kids, My Rockin’ Collection dexlue kits, our new Rock Detectives Mineral Mission kit, individual rocks, minerals, streak plates and hand magnifiers. Shopping for your classroom? All of our School Edition kits are ready for you! Shop now at www.MiniMeGeology.com!

Metamorphic Q&A

tracyb — Mon, 21 Sep 2009 13:14:05 +0000

Question: What rocks are changed by high pressure and high temperature?

Answer: The change of a rock by high temperature and pressure is called metamorphism. This is the process by which metamorphic rocks are formed. Any rock can be changed by metamorphic processes.

Keep your questions coming. Submit them to us here and look for a reply from us here on our blog and on our website!

New Shipment of Grossular Garnet has arrived!

tracyb — Thu, 10 Sep 2009 15:20:31 +0000

A new shipment of wonderful grossular garnet crystals have arrived. Beautiful grossular garnet mineral from Mexico is one of six varieties of garnet. Each single crystal shows the natural dodecahedral form of the garnet group. These samples, from Mexico, are approximately 0.75 to 1 inch in size. Sold singly.

Garnets are actually a family of minerals which are all very similar. These minerals are often found in metamorphic rocks such as schist. Garnet is fairly hard and is a 6.5 to 7.5 on the Mohs hardness scale which has a range from 1 (softest) to 10 (hardest). These minerals often form as dodecahedrons and trapezohedrons but can also form in groups or masses of crystals. Garnets have a colorless , a glassy luster, and will fracture if broken. There are actually six types of garnets:

almandine (red to violet red color)
spessartite (yellowish orange to reddish brown color)
pyrope (dark red color)
grossular (green yellow, reddish orange color)
andradite (colorless, yellow, green, or brown to black color)
uvarovite (brilliant green color)

The garnets which are often used as gemstones are typically a dark red color; however, the brilliant green of uvarovite is rare and very prized. Garnet is the birthstone of January and the gemstone of the second wedding anniversary.

Shop now for your new grossular garnet crystals!

Obsidian……Can you use it?

tracyb — Thu, 23 Jul 2009 12:37:42 +0000

Here is another Ask-a-Geologist that we received. Obsidian is one of our favorite rocks. Children love this rock too!

Question: What is obsidian rock used for?

Answer: In ancient times, obsidian was used to made crude knives and tools. Today, obsidian is used in the production of rock wool, knives and jewelry.

Have a question about geology or about being or becoming a geologist? Ask us!

For more great information about geology and to print fun puzzles visit www.MiniMeGeology.com and Dig Into Geology!