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As of 2019, GCM Industry and its affiliated companies have 5 advanced mining machine production bases and one production base under construction, with a total production area of 1,200,000 square meters, which can better meet more needs of global customers in the future.


Beginning in 1987, GCM industry has developed steadily and steadily in the field of mining machines, and has gradually formed a complete R&D, production, sales and service system.

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The Idaho 281 Star Garnet | Stewart's Gem Shop

The Idaho 281 Star Garnet. My father, Dudley Stewart, discovered the specific way in which to cut the rough garnet from the Emerald Creek area in order to reveal the star or rays within the stone. He pioneered the Idaho Star Garnet and introduced it into the market in 1951. In that same year Dudley hauled his finished Star Garnets to the 1951 ...

Gem Price Guide - International Gem Society - IGS

The IGS Gem Price Guide covers commonly traded colored gemstones as well as more unusual, collectible gems. The values listed below are based on a variety of sources, including primary and secondary gemstone dealers, jewelers, miners, and wholesale suppliers.

Gemstone Price Calculator | Reference Values of Gems - Gemval

Gemstone market average index (GVA) Gemval Aggregate index (GVA) has become a trusted benchmark for gemstone industry over years. It is calculated as a total value of 26 standard specimens of gemstone and represents the overall pricing trend in the jewellery market. Monitored by Gemval since 2005; Calculated as a percentage value relatively to 2005

Garnet Value, Price, and Jewelry Information

Garnets in rock, with poor external forms, may be much larger, such as the almandine from Gore Mountain, New York, which reaches a diameter of 60 cm. A few spessartites in Brazil have weighed several pounds and have retained great transparency and fine color.

Ant Hill Garnet? Tiny ants mine some of the best garnets!

Ant hill garnet rough: A specimen of ant hill garnet faceting rough from the Four Corners area of Arizona, under strong lighting to show its intense ruby-red color. This piece of rough weighs about 1.5 carats. Ant Hill Garnets as Diamond Indicators.

Agate Rough for sale | eBay

Red-pink Swali Agate Lapidary Rough From Mozambique 1 Pound Lot

Price per Carat for Colored Gemstones at AJS Gems

Most gemstones are priced according to weight, on a per carat basis. One gemstone carat is 200 milligrams, so there are 5 carats to the gram. But don't confuse carat, a measure of weight, with karat, a measure of gold purity.The price per carat of gemstones can varies enormously, literally from pennies a carat to tens of thousands of dollars.

Garnet Rough - Buy Garnet Rough Online | Gem Rock Auctions

Buy Garnet Rough. Garnet Rough is popular for professionals as well as amateur cutters as the rough represents good value for a clean stone-faceted or cab. It is easy to cut because the color is not dependent on the orientation of the rough. Further Reading. Colorful Garnet Gemstones To Suit Everyone's Taste

Garnet Gemstone | Garnet Stone – GIA

Many garnets are cut into standard shapes and standard sizes to allow easy setting into jewelry. This is especially true of many red garnets. Expensive garnets like fine-quality tsavorite are cut into shapes and cutting styles that allow more of the weight to be retained from the rough.

Garnet Information - Much more to it than flaming reds

Garnet is a very hard material and over the course of millions of years the surrounding rock can wear away and the remaining garnets can be washed down into streams where alluvial miners await. Garnets formed in much stronger rock or are younger geologically can be reached through shafts cut into mountains to reach the veins of crystals.

How to Value a Garnet | LEAFtv

You may be surprised to know that garnets actually come in every color except blue. The two kinds of green garnets called tsavorite and demantoid are rare and consequently more expensive than red garnets. Garnets are hard, durable and brilliant and are valued on carat weight, color, cut and clarity. The value is based on the factors as a whole.

How Much Do Garnet Stones Cost? |

Loose rough garnet stones can cost anywhere from $0.60 to $10 per carat. has a variety of garnet stones available for sale. For instance, a 0.05-carat demantoid garnet round mixed cut retails for $1,000, while a one-carat color-change garnet stone retails for $1,500.

Ruby Average Retail Prices (value charts per carat) in 2020

Market value charts; Data on Ruby is available for subscribers only. Subscribe. Ruby: average retail prices, Jun 2020. Ruby is famous for its intense red color. Its hardness (9 on Mohs scale) and durability make it the perfect choice for all kinds of jewelry, even the ones typically prone to damage from everyday wear, such as rings or bracelets ...

Uncut sapphire - worth anything?? | PriceScope Forum

Aug 21, 2019· Hello, So I am new to jewels, have been a precious metal collector for years. Went to a gem mine in Boone, NC last week and found 2 rubies, and a sapphire I am having cut. I also found this smooth, nicely shaped sapphire that I didn't want cut. It is shaped like an arrow head, beautifully...

How much are Garnets usually worth? | Yahoo Answers

May 19, 2007· When garnets are good enough to be cut the value depends on the type, the size, the clarity and quality of cutting. The cheapest are small almandine/pyrope types costing less than a dollar a carat (0.2gr.) up to fine green demantoid garnets costing up to $15,000 per carat or more.

Gemstone Market Value Charts (per carat) 2020 | USA Market ...

Market value charts Value charts: average retail prices, Jun 2020 For each gemstone, we provide a detailed and comprehensive value chart, which will help you evaluate its …

ø Blue Garnet | The Gemstone List ø

Blue Garnet Coloration. Blue garnet's color is due to high amounts of vanadium impurities (about 1% V 2 O 3 by weight) [4] and smaller amounts of chromium (0.14-0.36%). [5] Blue garnets with a stronger blue may contain more Vanadium - I have seen one lab report from a Madagascar blue garnet (purchased at the 2000 Tucson Gem Show) with 1.7% V. [6]

Rare Garnet Prices at AJS Gems - Gemstone

These rare garnets have been found in Kenya and Madagascar and prices range from about $500 to $3,000 per carat, depending on size, color and quality. See our Collection of Fine Color Change Garnets : Purple Garnet is a rare hybrid garnet found in East Africa. The finest material, from Mozambique, has an amazing vivid purple hue with red flashes.

Mahenge Garnets | PriceScope Forum

Sep 29, 2016· Dan Stair just finished up 2 Mahenge Garnets for me from some rough I sent him. Big one is 3.39 cts (9.58 rough) and the little one is 2.54 (8.10 rough). From the looks of the picture it looks like the little one came out better color and clarity wise, but I think I will be pleased with both.


Rough gem material is only the beginning of the story in evaluating the final product of the rough. The factors that determine the value are: Supply & demand, Time and money. Supply and Demand is the basic rule of evaluation in marketing any product. The larger the supply the less the demand which means a lower price.

how much is a raw garnet stone « BINQ Mining

APPRAISING ROUGH UNCUT GEMSTONES – HubPages. 29 Sep 2011 … How to determine the value of gem material in the rough state. … Gems stones other than diamonds sell maybe in the thousands of units in high …. Dark red garnet that is cut well runs from as little as $2 a carat to as hig as $50 a carat. … It comes out naturally blue (no green or yellow) and with much more …

Faceting Rough - How to evaluate and select it

Size can be "bad" if the rough won't support a stone that is marketable or that is "a good deal" after you count the cutting costs. For instance, a plain red Almandine Garnet rough weighing one gram will finish a gem weighing about one carat.

The Value of White Topaz | LEAFtv

White (or clear) is the most common color of topaz. The colorless variety generally has the least value, but stones can sell for $80 or more, depending on size and quality.

Gemstone Value: Price Per Carat for Precious Gems and ...

1: Gemstone Variety. Some gemstone varieties, such as sapphire, ruby, emerald, tsavorite garnet, tanzanite, spinel and alexandrite, command extremely high prices, due to their superior characteristics and rarity.Other varieties, such as many types of quartz, are abundant in many locations around the world, and prices are much lower.While the gem variety sets a general price range for a stone ...

How to Spot the Difference: Rubies and Garnets | The Loupe ...

Mar 30, 2015· Specifically, you don't want to pay for a ruby and wear a garnet. At a brief glance, they look very similar. However, rubies are considered one of the most valuable gemstones whereas garnets are, well, not. Rubies are harder, a much more brilliant red, and much more expensive. Consider these tips when examining your red gemstones: 1. Color

what is value of raw garnets « BINQ Mining

May 02, 2013· Gem Price per Carat – GemSelect. 13 Nov 2008 … Learn about the 10 factors that affect the price per carat of gemstones.… ruby, emerald, tsavorite garnet, tanzanite, spinel and alexandrite … ovals are usually cut to preserve as much weight of the raw material as possible. »More detailed

How to Identify Rough Gem Stones | Sciencing

For example, tiger eyes in the rough look like small rectangular multicolored banded blocks. Rough hematite can look just like 3/4-inch gravel in a driveway – gray – or be a dull solid black in angular shapes. Rough turquoise may appear as a band of turquoise blue in …

Polishing Garnets in a Rock Tumbler

2) Most garnet is not worth tumbling - including much of what is currently being sold as "garnet tumbling rough." Here are a few gemmy garnets that we tumbled. You will not find garnets like these being sold as tumbling rough for $10 or $20 per pound.