Santa Fe new Mexican. [volume] (Santa Fe, N.M.) 1898-1951, 1903-12-29
Many Interesting Papers Read Yes.
terday Before the Academy of
SCienCe-.AddreSSeS of We'll
come Tonight.-Program
for Tomorrow.
MeIanotekite.

MeIanotekite.
For example there is a leAdiron sill
cate, Melanotekite. found near Hills
boro which has heretofore been de-
scribed as a unique type from Sweden.
This mineral described in the Ameri-
can Journal of Science, August, 1898,
occurs in masses showing dry sur
faces in orthorhombic crystals
In Sweden this mineral occurs with
native lead, intimately mixed with
magnetic, and yellow garnet at Lang
ban in Wemland
. Hydroxincite.
In the Graphic mine of Kelly, near
Magdalena, has lately been found some
very high grade zinc ore. An eXamina-
tiop of this shows the mineral to be
Hydrozincite, another rare mineral.
This occurs as dark earthly masses
surrounding and forming the matrix
of some excellently crystallized Smith
ssonite in tabular rhombohedrons.
Turquoise.
Gem stones are rare in this Terri
y
ing considerable turquoise of excellent
quality in several localities. The oc-
7currence of this mineral in the Los
Cerrllos district near Santa Fe is in
thin seams and nodules in trachyte
In the Burro Mountains, south of Sill
yer City, the specimen | have from
that locality is rather granitoid
mixture of quartz and feldspar resem-
bling aplite or Alaskite The color is
very variable from shades of blue to
dark green and often of pale whitish
matriX OF little or no value. In fact
the value of turquoise depends largely
.pOn It's uniformity of color, its free
dom from flaws. limonite bands. etc.
and it's size. The cost of large per
feet specimens being much greater
than in tiny fragments. The name
turquoise is corruption of Turkey
the European source being originally
from the mines in Persia These mines
have furnished the sO-called Oriental
Turquoise" bringing until recently the
highest price and supposed to be the
finest in existence, but the supply is
now largely exhausted.
The stone has probably always been
known and used in ornamentation and
jewelry from very ancient times.
Crystalized turquoise is unknown. Its
structure is in some varieties fibrous
or in radiating bands but the mineral
occurs only in massive or cryptocry-
stalline form Possibly this lack of
crystallization may be traced to it's
varying composition but this is not at
all certain.
Caicite.
OF peculiar interest to mineralog-
ist are some twinned crystals of cal
cite from Hillsboro. Calcite, as every
one knows Is, next to quartz the most
abundant mineral in existence. In its
hexagonal crystallization some 200 diff
ferent forms are known. Generally
the crystallization is the scalenohedron
or rhombohedron or combinations OF
both, less frequently tabular, and in
the orthorhombie crystal, aragonite
acicular. Twinning is not uncommon
in calcite and this occurs according to
four laws.
The twinning of crystals is usually
detected b. reentrant angles. This
feature is important in identifying
twin crystals since it assists in orien,
tation of each individual and helps de.
termine the twinning axis and plane.
In the samples of scalenohedron cal
cites we have from Hillsboro twinning
occurs on OP (basal plane) and have
prepared a flattened projection of the
same to show the arrangement OF
planes, their situations, etc.
While this method of twinning is
not to be considered extremely rare, it
is rather unusual and is only in we'll
developed CRYSTALS in certain localities.
1t might occur on the simple scaleno-
hebron and not be detected owing to
attachment on the basal plane.
These Hillsboro twin calcites are
beautiful illustrations of crystal devel-
opment and the largest have now is
about eight inches in length.
Twinning forms one of the most fas.
cinating studies of crystallography and
have prepared a few figures to show
some prominent examples of this in
the several systems of crystallation.
Massicot.
In a recent trip to Silver City and
Chloride flats two miles west of Silver
City secured some interesting spe'
cimens Of the oxide Of lead, massicot
Dana does not record the occurrence
of this rare mineral in the United
States but in 1899 Foote of Philadel
phia discovered it in some old masses
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