Fieldtrip Report:

Diamond Hill Machine Dig!
Antreville, S.C.
April 2008

Report by: Rick Jacquot

In early April 2008, Chet Karwoski and a team of diggers from the area conducted an eight day machine dig in Antreville S.C. at the famous Diamond Hill quartz mine. This site has been mined/prospected for close to sixty years and has produced some of the most unusual quartz specimens in the world. The actual mine area covers approximately three acres of land. There are three main pits at the Diamond Hill Mine. The Skeletal pit, the Amethyst pit and the Smoky pit. Throughout the years, large iron stained skeletal crystals have been found in abundance by local collectors. The next most commonly found crystal would be the smoky quartz crystals. Mostly pale and cloudy, these were never the high quality smokies found in other areas of South Carolina. The rarest crystal to be found was the amethyst crystal. Very few have been found of any quality and nice large crystals that were undamaged were almost unheard of. The first major discovery of high quality quartz at Diamond Hill took place in October of 2005. Chet and his crew were conducting a joint dig with the members of the MAGMA club. The club was working the Skeletal and Amethyst pits while Chet and his workers were in the Smoky pit. On the afternoon of the second day of the dig, Dave Smith spotted a large cluster of smoky crystal in a collapsed pocket at the bottom of the pit. The crystals were covered with a thick iron coating that was later removed to reveal the finest phantom smoky/amethyst crystals to ever come from the mine and maybe the state! This discovery was documented in my May, 2006 article in Rock & Gem magazine entitled "Phenomenal Phantom Quartz". Since that time much collecting has taken place at the mine, many unusual discoveries have been made including the occassional amethyst crystal or cluster, but nothing significant since 2005. That all changed in April.

The dig started routinely as Chunky the machine operator was directed by the diggers to what everyone hoped was a good location. The team was rewarded early on with the discovery of a huge vein and pockets of amethyst. Not the usual material that has been produced in the past, but very large crystals, some up to 6" in diameter, the largest crystals ever found at the mine. Not only were we finding crystals, but huge plates covered with 2-6" amethyst crystals. The plates range in size from a few pounds to hundreds and even one that weighs around 1,000 pounds!

Road leading to the new discovery.

The area where we recovered some grape jelly colored large crystals in veins and as singles. Almost all the crystals that I have checked have enhydro inclusions as well as solid material in liquid trapped inside.

Mark and Steve

Once a specimen was unearthed, it was immediately wrapped and stored out of the sun to protect the crystals from heating and cracking.

Read and Bryan

Read Miner was our on site geologist for the dig. I asked Read to provide us with a brief description of the geology for the Diamond Hill Mine for this report, you will be seeing a more detailed geology report later 8^)

The Diamond Hill Quartz Crystal deposit is located near the Town of Antreville, South Carolina in Abbeville County. It is located along what geologists call, the Lowndesville sheer zone.
The Lowndesville sheer zone first developed several hundred million years ago as a small part of the formation of the Appalachian Mountains. Originally all of the continents on the earth were connected as one landmass called Gondwanaland. As the Earth continued to develop, this supercontinent broke up into several smaller continental masses that have migrated slowly across the globe. Periodically these continental masses have collided with each other. During these collisions, mountain ranges are formed. One of these mountain ranges is the Appalachian Mountains.

The core of the Appalachian Mountains were subjected to the highest heat and pressure resulting in very high grade metamorphic rocks. The Diamond Hill Quartz Deposit is located along the flanks of the Appalachian Mountain range in mid-grade metamorphic rocks, primarily gneiss and shist. More specifically, it is located in the Lowdesville sheer zone (LSZ).
The LSZ trends in a NE-SW direction through Laurens, Greenwood, and Abbeville counties of SC and continues into Georgia. The LSZ disappears in Laurens County, where the Kings Mountain belt picks up. The LSZ averages about three miles in width and is believed to be an area where huge blocks of rock from the southeast have been thrust over other more highly metamorphosed rock toward the northwest. Thrust zones are characterized by extensive faults that have shattered the rock along fault planes.

Evidence of this faulting is prevalent at the Diamond Hill quartz location. It is very common to find thin plates of fine drusy quartz crystals. These plates were chunks of rock that were shattered into thin plates as the earth was moving along these fault zones. Once the rock was shattered along these fault zones, hot hydrothermal water solutions (100-200 degrees centigrade) moved along these fault zones depositing drusy quartz crystals. At a later time, the hydrothermal water solutions became increasingly enriched in iron allowing the overgrowth of amethyst crystals in the larger vugs created by the earlier faulting.

Mark, Read, Bryan, Dave and Chet

Steve "all I found was purple"

Sandi Hill on the hill getting some pics of the dig.

We were finding a lot of amethyst, so much that I decided to bring Maggie over to haul some of the loot.

We filled the back of Maggie twice in three days with crystals and plates!

One of the large amethyst plates recovered, this one weighs around 120-150 pounds.

Page 2

Pages: (3) (4) (5) (6) (7) (8) (9) (10)

 

Back to fieldtrip menu