General types of fossil corals

Images of Yooperlites from Pebble beach, Marathon, Ontario

Yooperlites from Pebble beach, Marathon, Ontario

Yooperlites are an uncommon fine to coarse-grained gray igneous rock named syenite. It is composed mainly of alkali feldspar and ferromagnesian minerals such as hornblende.  Yooperlites are very ordinary looking igneous in normal but when exposed to long wave ultraviolet light has a fluorescent mineral is variety of sodalite, which glows orange.

           (Updated) A nicer photo with truer color.  Used my trusty 40 year old Raytech UV light.

Idaho Gemstones by County

Gemstone information is available for the following counties. Information comes from Gemstones of Idaho written by Alice Allebaugh. 
Reference: Idaho Lands website
(I'm reposting here because data has a way of disppearring off the internet.)

• ADAMS - Rubies and pink garnets are found at Rock Flat near New Meadows. Several diamonds have been found in this same area. Sapphires and corundum crystals that sometimes show asterism also have been found in the Rock Flat area.
• BLAINE - Amethyst is found near Hailey; copper, silver, lead and zinc minerals are abundant.
• BOUNDARY - Opal and opalized wood.
• CUSTER - Clear quartz, amethyst and citrine are found. Large geodes are common. Banded, red and yellow agate is scattered over the area. A forest of petrified wood is near Challis. Near the East Fork of the Salmon River is an excellent collecting locality where a variety of cryptocrystalline quartz is found in blood red sandstone. Near Challis a rare zeolite is found in greater abundance and better specimens than in any other known locality. Copper, silver, lead and zinc minerals are abundant.
• GEM - Fire opal is found in the lava beds of Squaw Butte near Emmett. The opals are salmon pink or cherry red in color and display great brilliance. Most are very small, but some have been large enough to cut into fine stones. Near the opal deposits agates of light blue color abound. Willow Creek has deposits of agatized and opalized wood of high quality as well as massive opal that ranges in color from deep red to salmon pink to white and pale blue.
• GOODING - Internationally famous "horse" fossil beds near Hagerman; opal and opalized wood.
• IDAHO - Nationally famous flora beds near Whitebird.
• LATAH - Common and fire opals have been found in the vesicular basalts. The internationally famous garnet diggings on Emerald Creek afford the collector an opportunity to find gem and star garnets in remarkably large sizes and quantities. Fossil plant remains can be found in many localities in the siltstone of the interbeds between basalt layers.
• LEMHI - Copper, silver, lead and zinc minerals are abundant
• LINCOLN - Opal and opalized wood.
• OWYHEE - Areas that yield red, yellow, green and mossy jasper of unexcelled quality. The area is nation-ally known for its pink and white plume agate and for its opal, both common and fire, which occurs in vesicles in the volcanic rocks. Banded, scenic, dendritic and sagenitic agates, as well as polka dot, smoky and moss agates are also found. Succor Creek on the western edge of the county yields red and green agates in a rich two-tone combination and a round shaped nodule, which is called "thunder egg." These are often found to be geodes with the center filled with fluids. In some the hollow center is lined with quartz crystals.
• SHOSHONE - Copper, silver, lead and zinc minerals are abundant
• WASHINGTON - Agates of many colors abound. The most highly prized agates are those that show an iridescence when cut into thin slabs. Petrified wood from Mann Creek northwest of Weiser is particularly beautiful. The grain of the wood is very prominent and the color is yellow, resembling natural oak. In the Beacon area west of Weiser the famous "Beacon Hill" nodules abound. These nodules are particularly beautiful because of the scenic or dendritic patterns. In some the interior is hollow and crystal lined.

Gemstone Guide for Idaho

This information comes Department of Lands website.
I'm reposting here because data has a way of disppearring off the internet.
(Reference: Information comes from Gemstones of Idaho written by Alice Allebaugh.)

GEMSTONE OR ROCK NAME	COUNTY	LOCATION
AGATES - NODULES Cryptocrystalline Quartz	CUSTER	• Lime Creek 12 miles south of Challis along US 93A • Iris along Willow Creek Road off US 93A south of Challis
	OWYHEE	• Squaw Creek
AGATES - PLUME Cryptocrystalline Quartz	OWYHEE	• Graveyard Point southwest of Homedale (private mine) west of US 95 near Idaho-Oregon border
AGATES - GREEN & GREEN MOSS Cryptocrystalline Quartz	BLAINE	• 9 miles north of Muldoon, south of Cary, along Little Wood River
	LEMHI	• Parker Mountain near Salmon
AGATES - BANDED & SCENIC Cryptocrystalline Quartz	LEMHI	• South of Meyers Cove
AGATES - LIGHT BLUE Cryptocrystalline Quartz	GEM	• Near Emmett
AGATES - RED Cryptocrystalline Quartz	CUSTER	• 3 miles west of Challis
AGATES - RED & GREEN Cryptocrystalline Quartz	OWYHEE	• Eastern fringe of Succor Creek
AGATIZED WOOD	CUSTER	• 12 miles south of Challis along US 93A
	WASHINGTON	• Hog Creek 8-10 miles northwest of Weiser
AMETHYST	BLAINE	• Pole Creek
	CUSTER	• Lost River
	OWYHEE	• War Eagle Mountain near Silver City • "Indian Bathtub" area
	VALLEY	• Paddy Flat and Big Creek area near Cascade
ANALCITE isometric zeolite mineral; last zeolite to be deposited.	BLAINE	• Golden Bell Mine in head of gulch containing Minnie Moore Mine near Bellevue
	CUSTER	• South of Challis
APATITE Calcium phosphate	CUSTER	• Blackbird Mining District
AQUAMARINE	ELMORE	• Above Atlanta
AZURITE Copper carbonate	ADAMS	• Seven Devils Mining District
	CUSTER	• Alder Creek and Bayhorse Mining Districts
	LATAH	• Hoodoo Mining District
	SHOSHONE	• Little North Fork area near Kellogg and Mullan
	OWYHEE	• South Mountain area
BERYL - GREEN	LATAH	• In pegmatites of the Levi Anderson, Muscovite and other mica mines near Avon
BERYL - DARK BLUE	ELMORE	• In primitive area near Atlanta
CALCITE - FLUORESCENT Calcium carbonate	CUSTER	• Alder Creek, Bayhorse and Yankee Fork Mining Districts
CALCITE - RHOMBOHEDRONS Calcium Carbonate	ADAMS	• White Mountain Mine, Seven Devils Mining District
	BLAINE	• Hailey (Mineral Hill) Mining District
CALCITE - MASSIVE / GRANULAR Calcium Carbonate	SHOSHONE	• Sunshine, Bunker Hill, Hypotheek, Hecla, Standard-Mammoth and Hercules Mines, Coeur d'Alene Mining District
CASSITERITE Tin Oxide	LEMHI	• Silver Creek • Panther Creek near junction of Moyer Creek, Cobalt area
	OWYHEE	• Along Jordan Creek near Silver City
CEYLONITE Spinel	BLAINE	• Wild Horse Canyon east side of Hyndman Peak
	ADAMS	• Rocky Flat area near New Meadows and Seven Devils Mining District
CHABAZITE Form of Zeolite	ADAMS	• Blue Jacket Mine, Seven Devils Mining District
	BOISE	• Warm Springs Creek area east of Boise
	ELMORE	• 5 miles below Glenns Ferry
CHALCEDONY - FLUORESCENT	TWIN FALLS	• Rabbit Springs on Idaho-Nevada border US 93
CHALCEDONY - VARIETIES	CUSTER	• Willow Creek Road south of Challis off US 93A • Mahogany Creek in Pahsimeroi Valley and near North Fork of Lost River
	OWYHEE	• War Eagle and Florida Mountain areas near Silver City
	BLAINE	• Pole Creek Summit near Galena and south of Carey along Little Wood River
	LATAH	• Potato Hill
	LEMHI	• Parker Mountain Mining District
	VALLEY	• Yellow Pine Mining District
CHRYSOCOLLA	BENEWAH	• Alder Creek
	ADAMS	• Arkansas Mine, et al., Seven Devils Mining District
	LATAH	• Hoodoo Mining District
	SHOSHONE	• Coeur d'Alene Mining District
CINNABAR	CUSTER	• Alder Creek Mining District
	VALLEY	• Yellow Pine Mining District
	WASHINGTON	• Near Weiser
CRYSTALS - COBALT	LEMHI	• Blackbird Mining District
	OWYHEE	• Silver City area
CRYSTALS - QUARTZ	CUSTER	• Near Bayhorse and in Yankee Fork Mining District
	BENEWAH	• Crystal Peak northeast of Fernwood
	IDAHO	• McKinley Gulch in Slate Creek and Ruby Meadows
	OWYHEE	• Long Gulch south of Silver City
	VALLEY	• Northwest of Donnelly
CORUNDUM	OWYHEE	• Near Silver City
	CLEARWATER	• Along Rhodes and Orofino Creeks near Pierce
	VALLEY	• Along Gold Fork Creek northeast of Donnelly
	ADAMS	• Rock Flat gold placers near New Meadows
	IDAHO	• Near (Resort) Burgdorf
DIAMONDS	ADAMS	• Little Goose Creek area near New Meadows
DOGTOOTH SPAR Calcite Crystals	IDAHO	• Adjacent to US 95 midway between Riggins and Lucile
EPIDOTE	ADAMS	• Peacock, Queen, Copper Boy and other mines, Seven Devils Mining District
	CLEARWATER	• Pierce area
	CUSTER	• Near Park Creek
	LEMHI	• Mackinaw and Carmen Creek Mining Districts
	OWYHEE	• Near Silver City
	VALLEY	• North of Paddy Flat Road northeast of Donnelly • Deep Creek north of McCall
FELDSPAR - MOONSTONE	CAMAS	• Near Fairfield
FELDSPAR - PALE YELLOW	BOISE	• Shafer Creek
FELDSPAR - CLEAR	FREMONT	• Crystal Butte 18 miles north of St. Anthony
FELDSPAR - VARIETIES	LEMHI	• Blackbird Mining District
	OWYHEE	• Silver City area
FLUORITE - PURPLE	CUSTER	• Empire Mine, Alder Creek Mining District
	LEHMI	• South of Meyers Cove
	VALLEY	• Stibnite
FOSSILS - SEE ZOISITE
GARNET - STAR	BENEWAH	• Purdue Creek, vicinity of Bovill and Clarkia and along East Fork of Emerald Creek (US Forest Service fee)
GARNET - LIME SILICATE	ADAMS	• Seven Devils Mining District
	BEAR LAKE	• Lanes Creek (NW 1/4, Section 9, Township 8 S, Range 43 E, BM)
	CUSTER	• Phi Kappa Canyon near head of Big Lost River • Copper Basin at head of East Fork of Big Lost River • Alder Creek Mining District near Mackay
GARNET - ROSE-RED BROWN-RED	CLEARWATER	• Rhodes Creek, Orofino area, near Clearwater River • Pierce area
	NEZ PERCE	• Clearwater River near Lewiston
GARNET - RED	SHOSHONE	• Canyon Creek • Purdue Creek
GARNET - PURPLE-RED	OWYHEE	• Silver City area
GARNET - YELLOW-GREEN	WASHINGTON	• Iron Mountain northeast of Weiser
GARNET - RED-PINK	ADAMS	• White Monument, Peacock and Copper Key mines near Kinney Point
	IDAHO	• On main Salmon River 10 miles above Riggins
HEDENBERGITE & ILVAITE	OWYHEE	• South Mountain Mining District
HEMATITE - PEBBLES	BANNOCK	• Lane's Creek gravel bars
	BOISE	• Boise Basin placers
HEMATITE	ADAMS	• Rock Flat on Goose Creek
	CUSTER	• In dumps of copper mines, Alder Creek Mining District
	LATAH	• Iron Mountain 20 miles north of Moscow
	WASHINGTON	• Iron Mountain
JADE	FREMONT	• Bitch Creek north of Tetonia
JASPER - RED WITH GREEN MALACHITE	BEAR LAKE	• Hummingbird Mine area in Paris Canyon near Montpelier
JASPER - BRUNEAU	OWYHEE	• 50 road miles south of Bruneau in Bruneau River Canyon
JASPER - VARIETIES	BLAINE	• South of Carey along Little Wood River
	CUSTER	• Crane Creek Reservoir area, 12 miles south of Challis along US 93A • Alder Creek Mining District near Mackay
	OWYHEE	• West of US 95 south of Homedale near Idaho-Oregon border
	WASHINGTON	• Signal Light 10 miles northwest of Weiser • Beacon Hill near Weiser
KYANITE	SHOSHONE	• Goat Mountain and Blackdome Peak area
MALACHITE	ADAMS	• Seven Devils Mining District
	BEAR LAKE	• Hummingbird Mine in Paris Canyon
	CUSTER	• Alder Creek Mining District
	FREMONT	• Skull Canyon area two miles east of Kaufman
	LATAH	• Hoodoo District
	SHOSHONE	• Coeur d'Alene and adjacent mining districts
MARCASITE	LEMHI	• 1 mile south of Salmon
	OWYHEE	• Associated with silver mines near Silver City
	SHOSHONE	• In the Gold Hunter Mine, Coeur d'Alene Mining District
MORDENITE	CUSTER	• 15 miles south of Challis
	LEMHI	• Near Salmon
MYRMEKITE	VALLEY	• Yellow Pine Mining District
NAUMANNITE	CUSTER	• Yankee Fork District
	LEMHI	• Parker Mountain Mines, Gravel Range Mining District
	OWYHEE	• DeLamar Mine on Florida Mountain near Silver City
OPAL - FIRE	CLARK	• Spencer Opal Mine near Spencer (private - fee charged)
	GEM	• Lava beds of Squaw Butte, Emmett area, and Black Canyon Dam
	LATAH	• 5 miles south of Forney on Opal Creek
	OWYHEE	• Near Givens Hot Springs, Oreana and on the west side of Squaw Creek
OPAL - BANDED	CUSTER	• 3 miles west of Challis
	OWYHEE	• Squaw Creek
OPAL - HYALITE	NEZ PERCE	• Near Lewiston area
OPAL - COLORED	GEM	• Red to salmon-pink to whites and pale blues along Willow Creek near Emmett
OPAL - VARIETIES	LEMHI	• Pahsimeroi Valley near May
OPAL - COMMON	CUSTER	• Poison Creek
	LATAH	• Moscow Opal Mines
	LEMHI	• Panther Creek • Pahsimeroi Valley near May
	NEZ PERCE	• Clearwater River Valley
	OWYHEE	• 17 miles south of Marsing • Castle Creek • Mule Springs • Givens Hot Springs area
OPALIZED WOOD	GOODING	• Clover Creek area
	LATAH	• Potlatch River Canyon, Kendrick area
	OWYHEE	• Few miles southeast of Hwy 95 at Idaho-Oregon state line in Coal Mine Basin (black opalized wood found in sandstone formation)
PROUSTITE	BLAINE	• Pilgrim Mine near head of Beaver Creek
	BOISE	• Banner Mining District
	BUTTE	• Hub Mine, Lava Creek Mining District
	OWYHEE	• War Eagle Mountain and Florida Mountain area near Silver City
	SHOSHONE	• Big Creek area
PETRIFIED WOOD	CUSTER	• Willow Creek Road south of Challis off US 93A • Malm Gulch area
	LINCOLN	• Clover Creek
	OWYHEE	• West of DeLamar off Jordan Valley Road • Middle reaches East Fork of Bruneau River • 9 miles south of Bruneau east of US 51 • Sands Basin
	WASHINGTON	• Manns Creek area near Weiser • Sage Creek near Weiser • Crane Creek area
PETRIFIED WOOD - BLACK	OWYHEE	• Coal Mine Basin on US 85 south of Marsing • Middle reaches East Fork Bruneau River 9 miles south of Coal Mine Basin on US 85 south of Marsing • Clover Creek area
	WASHINGTON	• Sage Creek northwest of Weiser
PYRITE	BLAINE	• Hailey Gold Belt
	BOISE	• Quartzburg area
	LEMHI	• Mackinaw Mining District
	SHOSHONE	• Coeur d'Alene Mine District
QUARTZ - CRYSTALS	BLAINE	• Pole Creek tributary of Little Wood River
	IDAHO	• Near Warren
	OWYHEE	• At mines near Silver City
	SHOSHONE	• On O'Donnell Creek near Stocking Meadows
	VALLEY	• Green Mountain area
QUARTZ - CLUSTERS	SHOSHONE	• Gem, Burke, Murray and Delta areas
QUARTZ - SMOKEY	ELMORE	• Dismal swamp northwest of Rocky Bar
	LEMHI	• Along Bandy Creek
	VALLEY	• Paddy Flats, Big Creek near Cascade
QUARTZ - GEODES	CUSTER	• Upper Valley of Lost River
	OWYHEE	• DeLamar Silver Mine area
	WASHINGTON	• Northwest of Weiser
QUARTZ - PSEUDOMORPHIC	BUTTE	• Lava Creek Mining District
	OWYHEE	• War Eagle and Florida Mountain areas near Silver City
RHODOCHROSITE	KOOTENAI	• Conjecture Mine south of Lakeview (REMARKS: PINK)
	LEMHI	• Blackbird Mining District and Kitty Burton Mine in Indian Creek District
RHODONITE	ADAMS	• South of New Meadows
RUBIES	ADAMS	• Placer deposits near New Meadows in Adams and Valley counties
	CLEARWATER	• Clearwater Drainage near Pierce
	OWYHEE	• DeLamar - Silver City area
	VALLEY	• Placer deposits near New Meadows in Adams and Valley counties
SAPPHIRES	ADAMS	• Rocky Flat area near New Meadows
	CLEARWATER	• Rhodes Creek near Pierce • Orofino Creek near Pierce
	VALLEY	• East slope of Brundage Mountain
SILLIMANITE Fibrolite	LEMHI	• Salmon River below Salmon
	NEZ PERCE	• Clearwater River Valley above Lewiston • Big Eddy of Clearwater River above Spaulding
STAUROLITE	BENEWAH	• 5 miles up Carpenter Creek from junction with St. Maries River
	SHOSHONE	• St. Joe Basin and along St. Joe - Clearwater Divide
STILBITE	ADAMS	• Blue Jacket Claim, Seven Devils Mining District
	BLAINE	• Minnie Moore Mine near Bellevue
	CUSTER	• North side of Galena Summit
THULITE Pink-colored Zoisite	ADAMS	• Seven Devils Mining District
THUNDER EGGS - AMETHYST LINED
	WASHINGTON	• Beacon Hill, Hog Creek, Weiser area
THUNDER EGGS - QUARTZ LINED	BUTTE	• Antelope Creek, Arco area • Road Creek, Arco area
	TWIN FALLS	• Rabbit Springs, US 93 Idaho-Nevada border
TOPAZ	ELMORE	• Dismal Swamp 9 1/2 miles northwest of Rocky Bar
TOPAZ - BLUE	VALLEY	• Along tributary of Paddy Creek in Paddy Flat area on Gold Fork Creek • Donnelly area
TOPAZ - YELLOW	CLARK	• Camas Creek
TOURMALINE	BLAINE	• South flank Hyndman Peak
	BOISE	• Boise Basin area
	CLEARWATER	• Pierce area
	LATAH	• Avon area
	LEMHI	• Blackbird Mining District
VALENCIANITE Adularia	CUSTER	• Yankee Fork District
	LEMHI	• Gravel Range and Parker Mountain District
	OWYHEE	• War Eagle and Florida Mountain near Silver City
WILLOWHITE	ADA	• Longhair Mine north of Eagle
ZEOLITES	CUSTER	• Various locations An interesting group of hydrated aluminous silicates.  Occurs as amygdular fillings in vesicles in basalt or amiosite flows; also as geode filling.  Thought deposited by hot waters at time of cooling of magmas.  Various locations in Owyhee and Custer counties.
	OWYHEE	• Various locations
ZIRCON	IDAHO	• Streams draining Idaho batholith, principally the American River near Elk City
ZOISITE (FOSSILS)	ADAMS	• Seven Devils Mining District
ZOISITE (FOSSILS) CAMBRIAN	BONNER	• In limy rock along southeast side of Pend Oreille Lake
	GOODING	• West rim of Snake River Canyon near Hagerman
ZOISITE (FOSSILS) MARINE	OWYHEE	• 9 miles south of Bruneau and to right of US 51
ZOISITE (FOSSILS) TEMPSKYA	BONNEVILLE	• 13 miles northwest of Hermans on Willow Creek
ZOISITE (FOSSILS) TRILOBITE	VALLEY	• South Fork of Gold Creek
ZOISITE (FOSSILS) GRAPTOLITES AND INVERTEBRATES	BLAINE	• Trail Creek east of Sun Valley
	CUSTER	• Shelves of Lost River Range • Bayhorse area north of Clayton
ZOISITE (FOSSILS) MOLLUSKS	CUSTER	• Bayhorse area
ZOISITE (FOSSILS) FISH	CUSTER	• Lost River Range near Mackay
ZOISITE (FOSSILS) MASTODON & MAMMOTH	LATAH	• In sediments of Snake River Plain as far north as Palouse Hills