20 TJie American Geologist. July, 189-7 
and disriii)ted mass of marble involved in eruptive diorite, side 
by side with an alteration of overlying eruptive directly in 
contact with the original calcareous mass. The altered erup- 
tive merges at both ends of the ferriferous portion insensibly 
into unaltered and non-epidotic diorite. Regarded as a sin- 
gle ore-body its maximum thickness was about 30 feet b}'' a- 
bout 100 feet in length and 40 feet in hight. It has practi- 
cally been worked out. But little material except of indiffer- 
ent quality, from excess of epidote, remains unbroken or a- 
mongst the refuse of the quarry. Shipments of 3,000 tons of 
ore from Texada to the works of the Puget Sound Iron Co. 
at Irondale, Washington, during a period of four years end- 
ing in 1888 were mainly from this quarry. 
This occurrence is thus described in detail because its char- 
acter is well exhibited by excavation. In conclusion, it may 
be remarked further that upon the steep flank of the syenite 
summit in front of the disrupted limestone belt, the connected 
ore-bod)^ lies in a lap of diorite in 'n position favorable to 
weathering action, but directly exposed to superficial erosion 
from which it has great!}' suffered, as attested by an abun- 
dance of heavy float strewn over the slope below. 
Development of ore by both modes of epigenesis is clearly 
attributable to the environment of a mass of limestone with 
basic eruptive, and to topographical conditions favorable for 
weathering action — of the nature of chemical permutations 
in place between soluble ferrous sulphates and alkaline carb- 
onates devele-ped by oxidation. Alteration in the diorite 
resulting in residual concentration of magnetic oxide seems 
to have taken place through primary development of ferric 
hydrate from epidote, this ferric silicate being as usual a sec- 
ondary product from weathering of amphibole and pyroxene. 
Within compass of the limestone, ferric hydrate, passing into 
ferric oxide and thence into magnetite, has likewise been devel- 
oped from hydrous ferrous carbonate, probably spontaneously, 
by double decomposition between ferrous salts -and calcic 
carbonate — ending in complete and stable ferriferous replace- 
ment of limestone. 
The Paxton ore body is a replacement of limestone, appar- 
ently complete, at the base of the same slope about one mile 
inland, rising to a hight of about 70 feet above the level of a 
