Identifying Dirk van Erp

Most Dirk van Erp hammered copper pieces are signed with his impressed windmill signature.  There are several variations of this windmill signature that help us determine the approximate date the piece was made.  The first variation of the famous windmill signature is pictured above. In September of 1909, Dirk van Erp partnered with interior designer D’Arcy Gaw and in February of 1910 they started using the impressed windmill signature that bears both of their names.  This variation was used from February of 1910 until January 30th, 1911 when their partnership was dissolved and D’Arcy Gaw’s name was removed. 

Early Dirk Van Erp Shell Casing Vases

So now we have covered all of the basic windmill signature variations, but what if a piece is unsigned?  Could it still be an unsigned Dirk van Erp piece?  Dirk van Erp worked in the Mare Island Naval Shipyard from 1900-1908.  He often brought home brass shell casings and hammered them into lovely vases which he gave to friends.  By 1907 he was selling them to art galleries in San Francisco such as Vickory, Atkins and Torrey.  But how do we know if a shell casing vase or trench art piece was made by Dirk van Erp?  First of all, there were 3 munition manufacturers that were predominanently used by the Mare Island Naval Shipyard: UMC Co of Bridgeport, CT; WNY or Washington Naval Yard; or Winchester Repeating Arms Co.  Most Dirk van Erp shell casings will have one of these three stamped on the bottom, but not all.  Some of his shell casing have no markings what-so-ever and others are by lesser known munition manufacturers.  Also, most of the dates when these munitions were made will be from the 1890s or up until about 1906.  They are often dated “8-98” for August 1898.  Here are some pictures of the three basic munition manufacturers.

During WWI, Dirk van Erp went backed to work at the shipyards, this time for Union Iron Works in San Francisco.  We do occasionally see examples of his shell casings will munition manufacturing dates reflective of WWI. 

The bottoms of most Dirk van Erp lamps and vases have inset copper bottoms that are often recessed about ¼”.  These bottoms often have what I call a “dimpled-dot” formation which we only see within his inset bottoms.  This “dimpled-dot” technique does not show up elsewhere in his metal, just on the bottoms. 

According to the patent filed by William van Erp in 1942, the Dirk van Erp windmill logo had been on continuous use since February 1910.  Since we know that Dirk van Erp and D’Arcy Gaw opened their studio in mid September 1909, there were some 5 months of production with no windmill stamp in San Francisco.  Prior to this, Dirk van Erp was making pieces in Oakland which were never signed.  The pictures that we have from the early San Francisco studio give us ample evidence of the forms he was producing as shown in this November 1909 photograph of the first San Francisco location at 376 Sutter Street.