Owens Valley Mining (Part 1) - Soapstone - An Unexpectedly Useful Material

The SPNG, originally the C&C, was built to move the mined and dry lake gathered minerals from the distant Inyo mountains and the Owens valley to market.  After the turn of the century, the SP standard gauge line was built to support the construction of the California Aqueduct, and once connected to Owenyo, provided a southward shipment path for the products of the SPNG to market.  Once the SPNG's northern connection over Montgomery Pass was abandoned in 1937, the standard gauge transfer at Owenyo was the only connection left.

Owens Valley, looking east at the Inyo Mountains

In this post, I want to look a little closer at one of the minerals that was shipped by Narrow Gauge rail to Owenyo, then loaded into Standard Gauge cars, and sent out to the larger world beyond Mojave.  While at the surface, most of the line's later loads were all white powder or solid chunk forms of 'stuff' which looked very much alike, there actually where about a dozen different minerals being worked.

SPNG 227 - low-side gondolas with bulk soapstone - owenyo_05_1940a_006_sml - owensvalleyhistory,com

In this view we see multiple low-side NG gondolas of bulk soapstone being unloaded by hand and wheelbarrow into standard gauge boxcars.  I'll be covering some of the other commodities in future dedicated posts.

But, What is Soapstone?

Several companies shipped soapstone and talc in several forms.  This explains why soapstone is seen on the Jawbone Branch moving in multiple types of freight cars, coming in on the Narrow Gauge to Owenyo in flat-bottomed gondola/flatcars, then moved over to bulk loading in Standard Gauge boxcars with chunks of 4-8" and finer pieces.  Specifically, I'm going to be looking at the soapstone which was loaded on a truck-ramp at Zurich, along with talc and soda ash... all white minerals which look similar, wonderful!  To be clear, talc does made up a large portion of soapstone, and some companies shipped the 'soapstone' deposits out to be used for its talc content, while others were intending to use the soapstone for it's unique qualities.

Soapstone samples - image from Wikipedia page, linked below.

The websites where I looked up Soapstone, it has a density of 2,980 kg/m³!  From this I am able to calculate how much weight we're usually seeing in the NG flat-bottomed gons, which were piled with soapstone, probably to capacity of 15-20 tons.  I can also figure how much they might be able to fit into a typical 40ft boxcar. 

Soapstone is useful for many products and consumable uses, including: marking pencils for metal which will be welded, multi-purpose carving for sculptures, high and wet area structural uses - such as - counter-tops, stoves, etc.  The Soapstone is a high concentration source of talc, with some silica and traces of CaO or Al2O3 mixed in.

By the mid-1950s, the SP Transfer Dock crews had a small forklift with a front-end bucket in place of the regular fork tines, to drop the loads of soapstone into piles in the boxcars.  Some comments on photos of the transfer trestle also report that soapstone was being moved in NG gondolas, then dumped into the SG gondolas at the trestle.

Boxcars or Gondolas?

SP 102856 post-war B-50-28 boxcar SPNG Owenyo Transfer Dock 1954, loading with 100 pound bags of Gypsum. - owensvalleyhistory,com s-l1600_ebay01_sml (Cropped)

A load in a 40ft AAR boxcar, 48in high of soapstone works out to about 48 tons.  The photo of SP 102856 has a half-height load of 100 pound bags, which would appear to be a full weight load as well.

 Seems that would be rather hard to put into a car with just the forklift bucket.  But it works out about right for a GS gondola piling to average about 4 feet high would be about right, as the cars had 5 foot high sides.

In Closing

SP boxcars of various classes are switched at Owenyo to load and move all the materials to and from the SPNG.

A couple of the photos in Joe Dale Morris's book on the Jawbone shows that most of the cars at the docks around the 1950s era were being loaded with the bucket forklift into the boxcars with the newer 7ft door boxcars (including foreign cars).  This might help explain why the sudden increase in B-50-28,29,30,31,33s showed up after the mid-1950s at Owenyo.  This would make since as using the bucket-forklift would be easier to maneuver into the car and dump the soapstone than the older 6ft door cars.

Jason Hill

Related Articles:

Jawbone Branch Index Page - Overview list of all my blog posts about the Jawbone Branch project.