Diamonds III

A Gallery of Natural Diamond Crystals

The gallery includes clear crystals and those exhibiting a range of colors (Figures 2-13), a range of shapes (Figures 2-15), examples of inclusions found in Diamonds (Figures 1-3), examples of shaping and etching by resorption (Figures 3-15), and examples of twinned diamonds (Figures-14,15).  Well-developed crystal forms, typical of diamonds, are shown in Figure 1. References to the impurity and structural defects as causes of differently colored diamonds, to twinning of diamonds, and their deposition including resorption can be found in DIAMONDS II.

Figure 1.  Crystal forms of native diamonds and the tetrahedral arrangement of carbon atoms in the crystal lattice [Ref 1].
Figure 2.  Pink cubic diamond crystals, Argyle mine, East Kimberley region, Western Australia [Ref 2]. Slight rounding and etching due to resorption is present [Ref 3].
Figure 3.  Colorless rounded dodecahedral diamond crystal, location not given [Ref 4].  Some rounding due to resorption is present [Ref 3].
Figure 4.  Rounded yellow octahedral diamond crystal (The Oppenheimer Diamond), Kimberley region, Republic of South Africa [Ref 5].  Rounding due to resorption is present [Ref 3].
Figure 5.  Octahedral diamond crystal with included garnet crystal [Ref 6].  Slight rounding of the octahedron’s corners is present due to resorption [Ref 3].
Figure 6.  Green clinopyroxene crystals in an irregular brown diamond, unstated location [Ref 7]. A large degree of rounding due to resorption is present [Ref 3].
Figure 7.  Sulfide mineral inclusions in octahedral diamonds and in a twinned crystal, Diavik mine, Northwest Territories, Canada [Ref 8].  A slight degree of rounding by resorption is present [Ref 3].
Figure 8.  Hydrogen inclusions appearing as a brown cloud in a diamond formed in liquid metal in the deep mantle of the earth [Ref 9].
Figure 9.  Diamond octahedrons shaped and etched by resorption [Ref 3], [Ref 10].
Figure 10.  Rounded brown diamond octahedron [Ref 3][Ref 11]
Figure 11.  Rounded green diamond octahedron [Ref 3],
[Ref 12].
Figure 12.  Rounded grey diamond octahedron  [Ref 3] [Ref 13]
Figure 13.  Rounded blue diamond rough [Ref 3]
[Ref 14] with cut gem.
Figure 14.  Rounded twinned crystal with some rounding.  [Ref 3]
[Ref 15] 
Figure 15.  Sixling diamond crystal formed by two interpenetrating diamond twins which are mutually twinned on octahedral planes; some rounding by resorption is present.  [Ref 3] [Ref 16]

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Meetings

When: 

3rd Friday of the month at 7:00 PM

Where: 

Summit Fire District Station 31
6425 N Cosnino Rd, Flagstaff, AZ
corner of Townsend-Winona & Cosnino roads

Agenda:
Along with the usual club business, the meetings consist of discussions of upcoming field trips, local club shows, ‘show and tell ‘of members’ recent finds and expositions. As always the club library is available for browsing and snacks for munching.
 
If you have questions please contact the President, Rob Cote, no at our email address coconinolapidaryclub@gmail.com.
 
Be sure to visit us on our Facebook page.

Fieldtrips

Fieldtrips are generally scheduled on the Saturday after the monthly meeting. The plans for the fieldtrip are discussed at that meeting. Details include time and location for caravaning to the search site, types and examples of specimens we’ll be looking for, location map, and any personal items needed for the exposition.
  
Anyone who plans on participating on the club sponsored trip needs to be a member.
 
January Fieldtrip
The club did not plan a trip for January. However, they agreed that the Quartzsite Show would be the destination for those who could make it. The show runs through January and February. Information for the show may be found if you Google “Quartzsite Gem and Mineral Showcase”.

Membership

Annual membership fee:
Individual – $20
Group/Family -$25