BUILDING AND ORNAMENTAL STONES. 481 



a reddish paste. It does not take a high polish, nor are its colors bril- 

 liant. The so-called Parmazo marbles, from the Miseglia, Pescina, and 

 Bacca del Frobbi quarries, are all white or whitish, and traversed by a 

 very coarse net-work of black or blue-black veins. 



The Yellow or Siena marbles are, next to the white statuary, probably 

 the most sought and widely-known of Italian marbles. Like the ma- 

 jority of foreign colored marbles, they are exceedingly fine-grained and 

 compact in texture, and take a high lustrous polish. The prevailing 

 color is bright yellow, though often blotched with slight purplish or 

 violet shades. When these darker veins or blotches prevail to a consid- 

 erable extent the stone is called Brocatelle. The most beautiful variety 

 of the Siena marble is obtained, according to Delesse, from Monte Arenti, 

 in Montagnola. It is of a uniform yellow color, but blocks of large size 

 can be obtained only rarely, and these often bring a price as high as $G 

 per cubic foot. The Brocatelle variety from the same locality is worth 

 only about two-thirds this sum. 



The Portor or Black and Gold marble. — This is, according to Delesse, 

 a black silicious limestone, traversed by yellowish, reddish, or brown 

 veins of carbonate of iron. It is brought chiefly from the Isle of Pal- 

 maria, in the Gulf of Spezia, and from Porto Yenere. A small amount 

 is also produced at Carrara and Serravezza. Blocks of this stone in 

 the National Museum show a good surface and high polish. It is 

 a beautiful stone, and the name black and gold well describes it. The 

 Portor marble, from the Monte d'Arma quarries, is a breccia of frag- 

 ments of black limestone with a yellowish cement. This is inclined 

 to break away in the process of dressing, thus rendering the produc- 

 tion of a perfect surface impossible without much filling. 



Black marble. — A fair variety of this material is brought from the 

 Colonnata quarries. The stone is not so dark as the Belgian black, 

 nor does it admit of so high a polish. 



Breccia marble. — The breccia marbles from Gragnana and Serravezza 

 I have never seen in use in this country, though they are stated to be 

 imported to a slight extent. The first-named consists of small bluish- 

 white fragments cemented closely by a chalk-red cement, while the 

 second variety has both white and red fragments similarly cemented. 



The Yellow marbles of Verona and Gragnana are entirely different in 

 appearance from those of Siena, being rather of a brownish hue, and 

 taking only a dull polish. They are compact rocks, excellently adapted 

 for decorative work. The so called red marble from the Oastel Poggio 

 quarries is rather a chocolate color, dull in polish, but pleasing to the 

 eye. 



Ruin marble. — This is a very compact yellowish or drab limestone, 

 the beds of which appear to have been fractured in every conceivable 

 direction by geological agencies, after which the resultant fragments 

 have become recemented by a calcareous or ferrugenous cement. The 

 rock is therefore really a breccia, although the proportional amount of 

 H. Mis. 170, p. 2 31 



