Indian Jewelers Supply Company (IJS) Reference Library

How To - Tips and Tricks

Books and Manuals

Safety

MSDS Reference

Conversion Tables and Calculators

Temperatures

Degrees Fahrenheit	ºF = (1.8 x ºC) + 32
Degrees Celsius	ºC = 0.556 x (ºF - 32)
ºCelsius	ºFahrenheit

Measures - Metric to Standard

ONE INCH	= 25.4 millimeters = 0.0254 meters = 0.02778 yards	"
ONE YARD	= 36 inches = 914.4 millimeters = 0.9144 meters	yd
ONE MILLIMETER	= 0.03937 inches = 0.00109 yards = 0.001 meters	mm
ONE METER	= 1000 millimeters = 39.3701 inchs = 1.09361 yards	m

Weights

ONE TROY OUNCE	= 31.1035 grams = 1.0971 avoirdupois ounces = 0.0686 avd. pounds = 20 pennyweights (dwts.)
ONE PENNYWEIGHT	= .05 troy ounces = 1.56 grams
ONE GRAM	= 5 carats = 0.64103 pennyweights (dwts) = .03527 avoir. ounces = 0.03215 troy ounces
ONE AVOIRDUPOIS OUNCE	= .91146 troy ounces = 28.3495 g = .0625 lb.
ONE AVOIRDUPOIS POUND	= 453.592 grams = 14.583 troy ounces

Inches to Decimal in Feet(ft)

One inch	1/12 ft	0.08 ft
Two inches	2/12 ft	0.17 ft
Three inches	3/12 ft	0.25 ft
Four inches	4/12 ft	0.33 ft
Five inches	5/12 ft	0.42 ft
Six inches	6/12 ft	0.50 ft
Seven inches	7/12 ft	0.58 ft
Eight inches	8/12 ft	0.67 ft
Nine inches	9/12 ft	0.75 ft
Ten inches	10/12 ft	0.83 ft
Eleven inches	11/12 ft	0.92 ft
Twelve inches	12/12 ft	1 ft

Melting Points — Precious And Base Metals

METAL	MELT POINT	METAL	MELT POINT
24K gold	1945ºF(1064ºC)	Copper, pure	1981ºF(1084ºC)
18K gold	1715ºF(936ºC)	Nickel, pure	2645ºF(1453ºC)
14K yellow gold	1615ºF(880ºC)	Tin, pure	450ºF(232ºC)
14K white gold	1825ºF(997ºC)	Zinc	787ºF(420ºC)
Fine (999) silver	1761ºF(961ºC)	Brass, yellow	1706ºF(931ºC)
Sterling(925) silver	1640ºF(894ºC)	#230 red brass	1877ºF(1026ºC)
Coin silver	1616ºF(881ºC)	#752 nickelsilver	1960ºF(1072ºC)

B&S Gauge in Inch & Millimeters

Ga.	In.	mm	Ga.	In.	mm
00	0.3648	9.266	17	0.04525	1.150
0	0.3249	8.252	18	0.04030	1.024
1	0.28930	7.348	19	0.03589	0.912
2	0.25763	6.543	20	0.03196	0.812
3	0.22942	5.827	21	0.02846	0.723
4	0.20431	5.189	22	0.02534	0.644
5	0.18194	4.620	23	0.02257	0.573
6	0.16202	4.115	24	0.02010	0.511
7	0.14428	3.665	25	0.01790	0.455
8	0.12849	3.264	26	0.01594	0.405
9	0.11443	2.906	27	0.01419	0.361
10	0.10189	2.588	28	0.01264	0.321
11	0.09074	2.305	30	0.01002	0.255
12	0.08080	2.035	31	0.00892	0.227
13	0.07196	1.828	32	0.00795	0.202
14	0.06408	1.628	33	0.00708	0.180
15	0.05706	1.450	34	0.00630	0.160
16	0.05082	1.291

Circle And Oval Geometry

Pi	= 3.1416
Circumference	The circumference of a circle is the distance around the outside. Circumference = Pi x Diameter
Diameter	The diameter of a circle is the distance across the circle, going through the exact center. Diameter = Circumference x .31831
Radius	The radius of a circle is the distance between the center and the outside edge.
Area of a Circle	Area of a circle is the amount of surface space that a circle consumes. Circle = Pi x Radius(squared)
Circle vs. Square	A circle is .7854 times as heavy as a square of the same size, i.e., the loss in cutting a circle from a square is .2146 of the weight of the square.
Area of an Oval	the longest diameter x the shortest x .7854

Metals Technical Data

Precious Metals

STERLING SILVER:	92.5% silver 7.5% copper Melts at 1640ºF
FINE SILVER:	99.9% silver Melting point 1761ºF
10K YELLOW GOLD:	41.666% gold Balance is: copper silver zinc silicon Melt point 1635ºF
14K YELLOW GOLD:	58.33% gold 8.3% silver 29.2% copper 4.17% zinc Melt point 1615ºF
14K WHITE GOLD:	58.33% gold 22.1% Copper 10.8% Nickel 8.77% Zinc Melt point 1800ºF/983ºC
18K YELLOW GOLD:	75% gold 15% silver 10% copper Melt point 1715ºF/527ºC
18K WHITE GOLD:	75.15% gold 17.3% Nickel 5.47% Zinc 2.08% Copper Melt point 1750ºF/955ºC
24K GOLD GRAIN:	(9999 fine)
MASTER ALLOY #383:	Used to reduce karat to 18-22K Melt temp at 18-22K is 1640ºF or 895ºC Recommended casting temperature is 1775ºF or 970ºC Silver Content is 55.20%
MASTER ALLOY #606:	Used to reduce 24K grain to 14-10k Melt temp at 14K is 1625ºF or 885ºC Melt temp at 10K is 1660ºF or 905ºC Recommended casting temp for 14k is 1775ºF or 970ºC Recommended casting temp for 10k is 1835ºF or 1000ºC Silver Content is 14.80%

Melting Points — Precious And Base Metals

METAL	MELT POINT	METAL	MELT POINT
24K gold	1945ºF(1064ºC)	Copper, pure	1981ºF(1084ºC)
18K gold	1715ºF(936ºC)	Nickel, pure	2645ºF(1453ºC)
14K yellow gold	1615ºF(880ºC)	Tin, pure	450ºF(232ºC)
14K white gold	1825ºF(997ºC)	Zinc	787ºF(420ºC)
Fine (999) silver	1761ºF(961ºC)	Brass, yellow	1706ºF(931ºC)
Sterling(925) silver	1640ºF(894ºC)	#230 red brass	1877ºF(1026ºC)
Coin silver	1616ºF(881ºC)	#752 nickelsilver	1960ºF(1072ºC)

Casting Bronzes

HERCULOY:	92% copper 4% silicon 4% zinc Melting point 1780ºF
BRONWITE:	59% copper 20% manganese 20% zinc 1% aluminum Melting point 1550ºF
DZR BRASS	63.0% copper 32.5% zinc 2.0% lead 0.7% silicon 0.5% manganese 0.5% nickel 0.5% tin 0.3% aluminum 0.05% antimony Melting range: 1610-1630ºF

Base Metals

NICKEL (CDA #752):	Also called German Silver or Nickel Silver 65% copper 18% nickel and 17% zinc Melting point 1960ºF
RED BRASS (CDA #230):	Also called Rich Low Brass, Jeweler’sBronze, Merlin’s Gold, or Craft Gold 85% copper with 15% zinc Melting point 1877ºF
COPPER (CDA #110):	99.9% copper Melting point 1981ºF
YELLOW BRASS (CDA #260):	70% copper 30% zinc Melt point 1706ºF

Laminates

10% SILVERFILLED:	10% layer of sterling silver (by weight) on nickel CDA #752
25% SILVERFILLED:	25% layer of sterling silver (by weight) on nickel CDA #752
1/20 12K GOLDFILLED:	5% layer of 12K gold (by weight) on red brass CDA #230
1/20 14K GOLDFILLED:	5% layer of 14K gold (by weight) on red brass CDA #230
SOLDER-FLUSHED GOLDFILLED SHEET:	Same as single-clad goldfilled, but has a layer of silver solder on the non-gold side Choose Rose – 1/10 10K Yellow – 1/10 10K Green – 1/10 14K

Ring Sizing Reference Guide

U.S. Standard Ring Sizes Inch and Millimeter measurements

Stretching Ring Shanks: Cast ring shanks can break if they are stretched excessively. The same is true where the ring is fabricated from sheet, or die-struck. Soldered seams are especially at risk. Annealing the metal, where practical, is a precaution to shank breakage. When in doubt, stretch no more than one-quarter to one-half a size.

SIZE	DIAM. (in)	LENGTH (in)	DIAM. (mm)	LENGTH (mm)
1	0.490”	1.54”	12.45mm	39.10mm
1-1/2	0.506”	1.59”	13.11mm	40.38mm
2	0.522”	1.64”	13.26mm	41.65mm
2-1/2	0.538”	1.69”	13.67mm	42.93mm
3	0.554”	1.74”	14.07mm	44.21mm
3-1/2	0.570”	1.79”	14.48mm	45.48mm
4	0.586”	1.84”	14.88mm	46.76mm
4-1/2	0.602”	1.89”	15.29mm	48.04mm
5	0.618”	1.94”	15.70mm	49.31mm
5-1/2	0.634”	1.99”	16.10mm	50.59mm
6	0.650”	2.04”	16.51mm	51.87mm
6-1/2	0.666”	2.09”	16.92mm	53.14mm
7	0.682”	2.14”	17.32mm	54.42mm
7-1/2	0.698”	2.19”	17.73mm	55.70mm
8	0.714”	2.24”	18.14mm	56.97mm
8-1/2	0.730”	2.29”	18.54mm	58.27mm
9	0.746”	2.34”	18.95mm	59.53mm
9-1/2	0.762”	2.39”	19.35mm	60.81mm
10	0.778”	2.44”	19.76mm	62.08mm
10-1/2	0.794”	2.49”	20.17mm	63.36mm
11	0.810”	2.54”	20.57mm	64.64mm
11-1/2	0.826”	2.59”	20.98mm	65.91mm
12	0.842”	2.65”	21.39mm	67.19mm

Gemstones

Glossary - Terms and Definitions

CARAT (CT)	Unit used to measure the weight of gems; one carat equals one fifth of a gram.
CLEARSHOT	Treated with clear resins.
COLORSHOT/STABILIZED	Treated with colored resins.
COMPRESSED	A treatment employing pressure.
ELJEN PROCESS	Treatment utilizing genuine turquoise to produce a harder stone, without stabilizing, enhancing, or reconstructing. It is considered the closest treatment to natural.
ENHANCED	Stone that has been electrochemically treated. No resins or dyes are used.
IMITATION	Any compound or mineral which is manufactured or treated so as to resemble a natural gemstone in appearance. Usually this term is not associated with labgrown and synthetic materials. Cubic zirconia can be classified as imitation diamond.
LAB GROWN	Like “synthetic”, describes artificially made substances that have all the physical properties and chemical composition of their natural counterparts.
MOHS’ SCALE	A standard scale used to measure the hardness of a stone. It runs from 1-10 , based on how easily a stone can be scratched.
NATURAL	Material which has not been chemically or otherwise altered. It usually excludes any backing materials.
ORGANIC GEM	Any gem originally formed from living animal or plant matter.
STABILIZATION	Resins are used to harden the stone and darken its color. Clearshot and Colorshot Turquoise are stabilized.
SYNTHETIC	A much-abused term. Synthetics are artificially made substances which have all the physical properties and the chemical composition of natural substances. Value is high.
TREATED	Vague term. Stones are treated to change coloration and hardness. Black Onyx and Carnelian are examples of treated stones, as are enhanced and stabilized Turquoise. Treated Turquoise is not usually identified by its place of origin.