1. 
   hornstone
   alternative name sometimes given to chert; also applied by some to other rocks such as hornfels, which is not treated in this document.
   Found op http://www.cst.cmich.edu/users/dietr1rv/gemrxAppB.htm
   
   
2. 
   Hornstone
   Horn'stone` noun (Min.) A siliceous stone, a variety of quartz, closely resembling flint, but more brittle; -- called also chert .
   Found op http://www.encyclo.co.uk/webster/H/62
   
   
3. 
   hornstone
   <chemical> A siliceous stone, a variety of quartz, closely resembling flint, but more brittle. ... Synonym: chert. ... Source: Websters Dictionary ... (01 Mar 1998) ...
   Found op http://www.mondofacto.com/facts/dictionary?hornstone
   
   
4. 
   Hornstone
   • (n.) A siliceous stone, a variety of quartz, closely resembling flint, but more brittle; -- called also chert.
   Found op http://thinkexist.com/dictionary/meaning/hornstone/
   
   
5. 
   hornstone
   1) Hornfels 2) Metamorphic rock
   Found op http://www.mijnwoordenboek.nl/EN/crossword-dictionary/hornstone/1
   
   

Tip: double click on a word to show its meaning.