Anchor Stone Blocks

Anchor Stone Blocks (German: Anker-Steinbaukasten) are components of stone construction sets made in Rudolstadt, Germany used as a construction toy.

Anchor Stone pieces originally were and are still made of a mixture of quartz sand, chalk, and linseed oil (German Patent 13,770; USA Patent 233,780), precisely pressed in molds so that they fit together perfectly. The stones come in three colors in imitation of the red brick, tan limestone, and blue slate of European buildings. They are not recommended for play by children under 3 years of age because of their small size. (CE No. 0494)

Anchor stones originated with the wooden building blocks which were designed by Friedrich Fröbel, the creator of the Kindergarten system. He observed how children enjoyed playing with geometrically shaped blocks.

The first Anchor Stone was produced when Otto Lilienthal and his brother Gustav decided that make a model of a stone building, using miniature blocks of stone. To this end, they started production of a limited number of blocks, made of a mixture of quartz sand, chalk, and linseed oil. Unfortunately, the Lilienthals, though brilliant inventors, had limited commercial success.

The stone blocks saw little popularity until 1880, when F. Ad. Richter, a wealthy businessman who had built a small empire in Rudolstadt, purchased the rights to the stone for 1000 marks (about €510), plus about 4800 marks (including 800 marks still owing) for the tooling and machines being used to produce them. He quickly developed a series of sets of individually packaged stones. The stone blocks sets quickly became popular. Thanks to advertising, during 1883 42,000 sets were sold. (Annual Report for 1883 of the Schwarzburg-Rudolstadt Factory Inspection Service, Archives, Heidecksburg, Rudolstadt) In 1894, Richter applied his "Anchor" trademark to the Richter's Anchor Stone Building Sets (Richters Anker-Steinbaukasten). The more than 600 different sets were produced over the multi-decade life of these sets; more than 1,000 stone shapes were made (CVA Stone Catalog). In 1910 Richter died, heralding the end of the first era for Anchor Stones. (Registered as death # 878 in Jena on December 27, 1910; he died at 9:00 PM on December 25, 1910.)

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