Quantcast
  Due to a new server, slow response may occur for which we apologize Portal logo
Login/Register
Bactrian Gold Treasure from Afghanistan, coming soon....
/gemstones/agricola_textbook_of_mineralogy/page_079 - 2
 

Book IV Sulphur, amber, Pliny's gems, jet, bitumen, naphtha, camphor, maltha, Samothracian gem, thracius stone, obsidianus stone

Book IV Sulphur, amber, Pliny's gems, jet, bitumen, naphtha, camphor, maltha, Samothracian gem, thracius stone, obsidianus stone Page of 251 Book IV Sulphur, amber, Pliny's gems, jet, bitumen, naphtha, camphor, maltha, Samothracian gem, thracius stone, obsidianus stone Text size:minus plus Restore normal size   Mail page  Print this page
BOOK IV
67
his authority—because it is said to be found on the island of Samothrace. Nicander calls it lapis thracius because farmers bring it from a Thracian river that they call Pontus. An unknown Greek writer states that the Pontus river which carries down this genus of stone is between Scytha and Medos. There is still a question whether lapis thracius may be the same stone as that which Theophrastus calls spinus or the same as another stone which I shall now describe. Each of these stones is bituminous but the latter is simple, spinus complex. I shall discuss the complex minerals in the tenth book.
Obsidianus lapis is a hard bitumen which is so named because it is found in Ethiopia near Obsidius. The gem called obsidiana is made from it. We see that one and the same thing, namely black earthy bitumen that is often hard when it comes from the earth, is known by all of these names. It is necessary that I be able to defend my opinion with the words of the writers themselves. But first may I describe this kind of bitumen.
This bitumen is black, pitchy and resembles a poor quality of coal. It has the luster of pitch and is sometimes soft, sometimes hard. Broken into splinters and set on fire it burns. When the soft variety is pulverized and placed in olive oil it dissolves rapidly, as Galen has written. I have purchased many of these stones, tabular and black and similar to the tab­lets that come from Coele, Syria, which, when placed in a fire, burn with a meager flame. These come from the hills around the Dead Sea and from the same locality that produces bitumen. Their odor is similar to that of bitumen. However, without doubt the hot waters flowing deep beneath those bituminous hills have abraded and liquefied the bitumen and carried it into the lake or sea in which these waters have welled up as springs. This black bitumen is later cast up by the raging and seething of the sea and is found on the shores. It differs from the true Judean bitumen only in hardness. The more broken material is not tabular but differs only in this respect.
Ampelitis earth, which is also called pharmacist's earth (pharmacitis) is the best. It is pitch black and when broken into small splinters has the same luster as small pieces of coal. It dissolves when crushed and mixed with olive oil, according to Dioscorides. Galen says that it differs greatly from other earths and comes near to being the essence of stone. From this we know it to be hard. It is known to consist of bitumen, not so much from the writings of Pliny who says that it is very similar to bitumen as from the writings of Posidonius who says that it is bituminous. Since it is such a material it burns readily. From all of these facts it is evident that ampelitis earth is native bitumen of the finest quality and for that reason is given preference by physicians. Bitumen that has been mixed with too much earth is usually of another color and does not belong to this group.
It is obvious to the eyes that native coal does not differ from ampelitis earth. Theophrastus who has referred to coal makes no reference to ampe­litis and, on the other hand, those who have written about ampelitis have
Book IV Sulphur, amber, Pliny's gems, jet, bitumen, naphtha, camphor, maltha, Samothracian gem, thracius stone, obsidianus stone Page of 251 Book IV Sulphur, amber, Pliny's gems, jet, bitumen, naphtha, camphor, maltha, Samothracian gem, thracius stone, obsidianus stone
Suggested Illustrations
Other Chapters you may find useful
Other Books on this topic
bullet Tag
This Page