Silver City, Kansas

Micro-Lite Mine

James S. and Susan W. Aber

**Table of contents**
Introduction	2009 venture
2012 venture	2015 venture
Related sites	References

Introduction

Silver City is the name of a geological feature in Woodson County near the town of Buffalo, southeastern Kansas. For more than three decades, we have led annual field trips to this site for geology students at Emporia State University in order to collect a variety of unusual igneous and metamorphic rocks and minerals.

The name Silver City dates from the 1870s, when prospectors thought that silver was present. This led to a short-lived mining boom and swindle, as there is no silver. Instead, a rare rock called lamproite (lamprophyre) is found here. It was emplaced as an intrusive pipe-and-sill structure during the late Cretaceous (~90 million years ago), and the adjacent sedimentary rocks were altered by contact metamorphism and hydrothermal circulation (Wojcik and Knapp 1990; Aber and Aber 2001).

The Silver City lamproite is closely related to the nearby Rose Dome intrusion, also in Woodson County, as well as similar intrusive pipes at Smoky Butte, Montana and West Kimberley, Australia (Cullers and Berendsen 2011). In other parts of the world, lamproite contains diamonds, but none are known here. The lamproite is mined nowadays in an open pit for a commercial product named Micro-Lite, which is used as a cattle-feed supplement.

Left: Micro-Lite sign on U.S. highway 75 at Buffalo, Kansas.
Right: street sign on the road leading to the Micro-Lite plant.

2009 venture

In November 2009 the authors accomplished kite aerial photography under high-wind conditions. For this venture, we were assisted by Lynn Lefebvre, an undergraduate student. After many visits and years of ground study, this was our first successful KAP at Silver City.

The day of our visit was forecast to have strong south to southwest wind at 20-30 mph, and the forecast proved to be accurate! We set up on the southern rim of the mine pit and utilized a small delta kite to lift our Canon S70 and Rebel 300 SRL camera rigs. The former has a wide-angle lens; the latter was equiped with a superwide-angle lens. The delta performed remarkably well, considering the gusty wind. The delta lifted both rigs and was relatively stable in flight.

**Canon Rebel 300 views over Silver City**
View toward SE	View toward SW	View westward	View northward	View toward NE

Canon S70 views over Silver City
Ore processing equipment, storage silo, maintenance buildings and office complex on the southern side of the open-pit mine. View toward southeast.
Eastern portion of the open-pit mine. This section was worked most recently prior to our visit. The lamproite is excavated using earth movers to scrap up the soft, clayey rock.
View toward southern margin of the mine. Kite flyers are set up on the rim at the van near center of view. Note kite line.
Westward view of the mine pit and surroundings. Drainage channels are cut through the wall rocks toward upper left and at the far end.
View toward the northwest showing the northern wall of the open-pit mine. Note the cluster of students on the mine wall at scene center.

Near-vertical shots Left: students on the northern wall of the open-pit mine. They are searching for various minerals in the contact metamorphic rocks adjacent to the intrusion. Right: Tracks in the lamproite were made by earth movers.

**Canon S70 views over Silver City**
	Ore processing equipment, storage silo, maintenance buildings and office complex on the southern side of the open-pit mine. View toward southeast.
	Eastern portion of the open-pit mine. This section was worked most recently prior to our visit. The lamproite is excavated using earth movers to scrap up the soft, clayey rock.
	View toward southern margin of the mine. Kite flyers are set up on the rim at the van near center of view. Note kite line.
	Westward view of the mine pit and surroundings. Drainage channels are cut through the wall rocks toward upper left and at the far end.
	View toward the northwest showing the northern wall of the open-pit mine. Note the cluster of students on the mine wall at scene center.

2012 venture

Another KAP opportunity came about in April 2012 with nearly ideal weather conditions—sunny sky, temperature about 70 °F, and southeast wind 10-20 mph. We flew a large rokkaku, again with the Canon S70 camera rig as well as a newer Rebel 1000 SLR camera rig equiped with a superwide-angle lens. Gayla Corley and Megan Sprague assisted with this venture.

We noticed the mining operation had expanded eastward considerably since 2009. A mild winter and warm spring had caused early greening of the winter wheat, grass and trees in the surrounding landscape.

**Canon Rebel 1000 views over Silver City**
View eastward	View toward NE	View northward	View toward NW	View westward

Canon S70 views over Silver City
Left:: overview of kite flying site on the southern margin of the mine. Kite flyers just below scene center. Right: self-portrait of kite flyers: JSA (left), Megan Sprague (center), and Gayla Corley (right).
Views over the mine. Left: looking northward. Note people to left side. Right: looking westward with a person in lower right corner.

2015 venture

In early April, we again visited the Silver City mine to conduct aerial photography. We attempted to fly the large rokkaku, but wind was variable and too light to sustain kite and camera rig in flight. So we launched a small helium blimp, first with an automatic camera rig (Canon Elph), and then with a radio-controlled camera rig (GPS Nikon).

	Overviews of the mine site to the east (left) and west (right). The eastern portion is newer, having been excavated during the past few years. The older western side has been dug out for several decades and is deeper. Both portions continue to be worked as shown by earthmover tracks.
	Close-up shots of the processing plant, storage silo, service and office buildings, and heavy equipment. The mine was not operating, so earthmover and bulldozer are parked for the day.
	Spring burning of tallgrass prairie and oak forest understory in the surrrounding Chautauqua Hills vicinity. By the end of the day heavy smoke and ashes covered the terrain across a large portion of eastern Kansas.

Related websites

Geologic guidebook from the Kansas Geological Survey.
Silver City geology field trip from Emporia State University.
USGS Mineral Resources—Silver City lamproite.
Silver City ghost town.

References

Aber, J.S. and Aber, S.W. 2001. Limestone xenoliths in Hills Pond Lamproite, Woodson County, Kansas. Transactions of the Kansas Academy of Science 104, 1/2. Access online at JSTOR.
Cullers, R.L. and Berendsen, P. 2011. Mineralogical and chemical evolution of lamproites in Woodson and Wilson Counties, southeastern Kansas. Kansas Geological Survey, Technical Series 22, 38 p. Access online at KGS.
Wojcik, K.M. and Knapp, R.W. 1990. Stratigraphic control of the Hills Pond lamproite, Silver City Dome, southeastern Kansas. Geology 18/3, p. 252-254. Access online at GSA.

Return to KAP gallery.
Last update: October 2018.

	Left:: overview of kite flying site on the southern margin of the mine. Kite flyers just below scene center. Right: self-portrait of kite flyers: JSA (left), Megan Sprague (center), and Gayla Corley (right).
	Views over the mine. Left: looking northward. Note people to left side. Right: looking westward with a person in lower right corner.