Upcoming Auctions Auctions Near Me How Auctions Work

|

Help Consign Price Results

Explore Categories

Art
Drawings
Mixed Media & Collages
Paintings
Photography
Prints & Multiples
Scrolls, Screens & Fan Paintings
Sculptures
Statues & Statuettes
Artists
Andy Warhol
Banksy
Francis Bacon
Frank Stella
Jean-Michel Basquiat
Keith Haring
Pablo Picasso
Roy Lichtenstein
Popular Searches
Bronze Statues
Folk Art
Lithographs
Oil Paintings
Pencil Drawings
Portraits
Browse by Origin
African
American
Ancient Egyptian
Ancient Greek and Roman
Asian
Catholic
Egyptian
European
Middle Eastern
Oceanic/Pacific Rim

Jewelry
Bracelets
Brooches & Pins
Cufflinks, Tie Pins & Tie Clips
Earrings
Loose Stones & Beads
Necklaces & Pendants
Rings
Watches
Featured
Bulgari
Bulova
Cartier
Chanel
Chopard
Omega
Patek Philippe
Rolex
Swarovski
Tiffany & Co.
Van Cleef & Arpels
Popular Searches
18K Gold Jewelry
Diamond Jewelry
Emeralds
Pearls
Rubies
Sapphires

Asian Antiques
Art
Collectibles
Fashion
Furniture
Jewelry
Tableware & Barware
Vases & Garnitures
Browse By Origin
Chinese Antiques
Indian Antiques
Japanese Antiques
Korean Antiques
Persian Antiques
Southeast Asian Antiques
Tibetan Antiques
Featured
Bronze
Cloisonne
Han Dynasty
Jade Jewelry
Ming Dynasty
Porcelain
Qing Dynasty
Woodblock Prints

Furniture
Beds & Headboards
Cabinets & Storage
Seating
Tables
Tables
Coffee & Cocktail Tables
Desks & Writing Tables
Dining Tables
Seating
Benches
Chairs
Sofas & Settees
Cabinets & Storage
Armoires & Wardrobes
Bookcases, Display Cases & Shelves
Buffets, Sideboards & Credenzas
Dressers & Chests of Drawers
Browse By Styles
Art Deco
Chippendale
Federal Style
Hollywood Regency
Mid-Century Modern
Mission Style
Queen Anne
Rococo
Victorian
Featured
Eames Chairs
George Nelson
Hans Wegner
Herman Miller
Milo Baughman
Paul Evans
Stickley

Collectibles
Advertisements & Signs
Automobilia & Petroliana
Banks, Registers & Vending Machines
Books, Magazines & Papers
Breweriana & Beer Collectibles
Cameras & Photo Equipment
Coins, Currency & Stamps
Figurines & Miniatures

Desk Accessories
Hardware
Hunting & Fishing
Maps & Atlases
Musical Instruments
Radios, Phones & Electronics
Railroad Collectibles
Religious & Spiritual Objects
Rocks, Minerals & Fossils

Scientific & Medical Objects
Tobacciana
Toys & Hobbies
Vanity, Perfume & Grooming
Weapons & Armor
Wine & Spirits

Coins
Bills & Currency Notes
Bullion
Coins
Exonumia
Stamps
Stocks, Bonds & Bank Certificates
Browse By Origin
African
American
Ancient Greek and Roman
Asian
Byzantine
Egyptian
European
Middle Eastern
Oceanic/Pacific Rim
Featured Coins
Commemoratives
Dollars & Half Dollars
Gold Coins
Half-Dimes and Dimes
Nickels
Proof Sets
Quarters

Home & Décor
Candle Holders
Clocks
Decorative Baskets
Fireplaces & Mantels
Fireplace Accessories
Garden Ornaments & Accents
Kitchenware
Lighting
Outdoor & Patio Furniture
Picture Frames

Coat Racks & Umbrella Stands
Magazine Racks
Mirrors
Planters, Cachepots & Jardinieres
Rugs & Carpets
Tableware & Barware
Textiles & Linens
Vases & Vessels
Featured
Art Glass
Baccarat
KPM
Lalique
Limoges
Meissen
Murano
Rookwood
Sèvres
Tiffany Studios

Clothing
Dresses & Gowns
Jackets & Coats
Pants & Trousers
Robes & Kimonos
Shirts & Blouses
Skirts
Suits & Ensembles
Sweaters
Vests
Accessories
Bags & Purses
Belts & Chatelaines
Canes & Walking Sticks
Eyeglasses & Spectacles
Neckties, Bowties & Bolo Ties
Pocket Squares
Scarves, Wraps & Shawls
Shoes
Wallets & Money Clips
Featured Designers
Chanel
Chloe
Christian Dior
Gucci
Hermes
Louis Vuitton
Michael Kors
Yves Saint Laurent

Loose Stones & Beads

3.83 Ct Natural 31 Drilled Multi-color Fire Opal Loose Beads First Image

#image-loader-main { display: none; }

3.83 Ct Natural 31 Drilled Multi-color Fire Opal Loose Beads First Image

3.83 Ct Natural 31 Drilled Multi-color Fire Opal Loose Beads

Total Sales0 Sold

Median Sale Price

Sale Price Range

You May Also Like

CERTIFIED 17.8 CT NATURAL COLOR OPAL LOOSE STONE (1 of 6)

CERTIFIED 17.8 CT NATURAL COLOR OPAL LOOSE STONE

iStone Jewelry Co LTD

See Sold Price

Feb 29, 2024

23.40 Ctw Natural Blue Topaz Oval Cut Certified Natural Gemstones (1 of 2)

23.40 Ctw Natural Blue Topaz Oval Cut Certified Natural Gemstones

See Sold Price

Mar 06, 2024

10.48 Ct Natural Purple Amethyst Loose Stone (1 of 2)

10.48 Ct Natural Purple Amethyst Loose Stone

See Sold Price

Mar 13, 2024

9.82 Ct Natural Six Line Star Ruby Loose Stone Certified Natural Gemstones (1 of 2)

9.82 Ct Natural Six Line Star Ruby Loose Stone Certified Natural Gemstones

See Sold Price

Mar 06, 2024

6.04 Ct Natural Six Line Star Ruby Loose Stone Certified Natural Gemstones (1 of 2)

6.04 Ct Natural Six Line Star Ruby Loose Stone Certified Natural Gemstones

See Sold Price

Mar 06, 2024

9.09 Ct Natural Purple Amethyst Loose Stone (1 of 3)

9.09 Ct Natural Purple Amethyst Loose Stone

See Sold Price

Feb 28, 2024

17.57 Ct Natural Malachite Loose Stone (1 of 2)

17.57 Ct Natural Malachite Loose Stone

See Sold Price

Feb 28, 2024

6.11 Ct Natural Blue Topaz Loose Stone (1 of 2)

6.11 Ct Natural Blue Topaz Loose Stone

See Sold Price

Mar 13, 2024

2.35 Ctw Natural Zambian Emerald Cushion Cut Certified Natural Gemstones (1 of 2)

2.35 Ctw Natural Zambian Emerald Cushion Cut Certified Natural Gemstones

See Sold Price

Mar 06, 2024

2.73 Ctw Natural Zambian Emerald Octagon Cut Certified Natural Gemstones (1 of 2)

2.73 Ctw Natural Zambian Emerald Octagon Cut Certified Natural Gemstones

See Sold Price

Mar 06, 2024

53.73 Ct Natural Blue Turquoise Loose Stone (1 of 2)

53.73 Ct Natural Blue Turquoise Loose Stone

See Sold Price

Feb 28, 2024

20.00 Ctw Natural Purple Amethyst Oval Cut Certified Natural Gemstones (1 of 2)

20.00 Ctw Natural Purple Amethyst Oval Cut Certified Natural Gemstones

See Sold Price

Mar 06, 2024

38.23 Ct Natural 191 Drilled Pink Sapphire Loose Beads Certified Natural Gemstones (1 of 3)

38.23 Ct Natural 191 Drilled Pink Sapphire Loose Beads Certified Natural Gemstones

See Sold Price

Mar 06, 2024

66.46 Ct Natural 168 Emerald Loose Beads Certified Natural Gemstones (1 of 3)

66.46 Ct Natural 168 Emerald Loose Beads Certified Natural Gemstones

See Sold Price

Mar 06, 2024

38.39 Ct Natural Purple Amethyst Set Loose Stones Certified Natural Gemstones (1 of 2)

38.39 Ct Natural Purple Amethyst Set Loose Stones Certified Natural Gemstones

See Sold Price

Mar 06, 2024

21.68 Ctw Natural Zambian Emerald Round Cut Certified Natural Gemstones (1 of 4)

21.68 Ctw Natural Zambian Emerald Round Cut Certified Natural Gemstones

See Sold Price

Mar 06, 2024

Similar Sale History

Unlock All Prices

Sold

2.31 Ct Natural 5 Drilled Multi-Color Fire Opal (1 of 2)

2.31 Ct Natural 5 Drilled Multi-Color Fire Opal No Reserve! Title: 2.31 Ct Natural 5 Drilled Multi-Color Fire Opal Unshaped beads Stone Clarity: Transparent Gemstones: Natural Opal Beads Carat Weights: 2.31 Size/Dimensions: 7.5x3.0 - 11.0x4.5 mm/ 5

See Sold Price

Sold

6.31 Ct Natural 26 Drilled Round Multi-Color Fire Opal (1 of 2)

6.31 Ct Natural 26 Drilled Round Multi-Color Fire Opal No Reserve! Title: 6.31 Ct Natural 26 Drilled Round Multi-Color Fire Opal Beads Stone Clarity: Transparent Gemstones: Natural Fire Opal Beads Carat Weights: 6.31 Size/Dimensions: 4.30 to 4.50 mm / 26

See Sold Price

Sold

5.31 Ct Natural 17 Drilled Multi-Color Faceted Fire (1 of 2)

5.31 Ct Natural 17 Drilled Multi-Color Faceted Fire No Reserve! Title: 5.31 Ct Natural 17 Drilled Multi-Color Faceted Fire Opal Beads Color/Clarity: Transparent Gemstone: Natural Faceted Opal Beads Carat Weight: 5.31 Size/Dimensions: 4.00 to 4.70 mm /

See Sold Price

Sold

5.31 Ct Natural 10 Drilled Multi-Color Faceted Fire (1 of 2)

5.31 Ct Natural 10 Drilled Multi-Color Faceted Fire No Reserve! Title: 5.31 Ct Natural 10 Drilled Multi-Color Faceted Fire Opal Beads Stone Clarity: Transparent Gemstones: Natural Faceted Opal Beads Carat Weights: 5.31 Size/Dimensions: 5.30 to 6.10 mm

See Sold Price

Sold

4.70 Ct Genuine 31 Drilled Multi-Color Fire Opal Beads (1 of 2)

4.70 Ct Genuine 31 Drilled Multi-Color Fire Opal Beads No Reserve! Title: 4.70 Ct Genuine 31 Drilled Multi-Color Fire Opal Beads Stone Clarity: Transparent Gemstones: Natural Opal Beads Carat Weights: 4.70 Size/Dimensions: 3.40 to 4.00 mm / 31 PC's Additi

See Sold Price

Sold

3.83 Ct Genuine 17 Loose Drilled Round Multi-Color Fire (1 of 3)

3.83 Ct Genuine 17 Loose Drilled Round Multi-Color Fire Item: 3.83 Ct Genuine 17 Loose Drilled Round Multi-Color Fire Opal Beads Loose Gemstone: Natural Opal Beads Stone Clarity: Transparent Carat Weight: 3.83 Size/Dimensions: 3.8 to 4.8 mm / 17 PC's Top F

See Sold Price

Sold

3.83 Ct Genuine 61 Drilled Round Multi-Color Fire Opal (1 of 2)

3.83 Ct Genuine 61 Drilled Round Multi-Color Fire Opal No Reserve! Title: 3.83 Ct Genuine 61 Drilled Round Multi-Color Fire Opal Beads Stone Clarity: Transparent Gemstones: Natural Opal Beads Carat Weights: 3.83 Size/Dimensions: 2.60 to 3.30 mm / 61 PC's

See Sold Price

Sold

6.31 Ct Natural 11 Drilled Faceted Fire Opal Beads (1 of 2)

6.31 Ct Natural 11 Drilled Faceted Fire Opal Beads Weight - 6.31 Ct / Size - 5.50 to 5.70 mm / Pices - 11 No's / Shape - Round / Color - Multi-Color / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

1.00 Ct Natural Drilled Multi-color Fire Opal Loose Beads (1 of 2)

1.00 Ct Natural Drilled Multi-color Fire Opal Loose Beads Weight - 1.00 Ct / Size - 6.90 x 6.90 / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

1.09 Ct Natural Drilled Multi-color Fire Opal Loose Beads (1 of 2)

1.09 Ct Natural Drilled Multi-color Fire Opal Loose Beads Weight - 1.09 Ct / Size - 7.00 x 7.00 mm / Pieces - 1 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

0.82 Ct Natural Drilled Multi-color Fire Opal Loose Beads (1 of 2)

0.82 Ct Natural Drilled Multi-color Fire Opal Loose Beads Weight - 0.82 Ct / Size - 6.90 x 6.90 mm / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

6.47 Ct Natural 19 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

6.47 Ct Natural 19 Drilled Multi-color Fire Opal Loose Beads Weight - 6.47 Ct / Size - 5.00 - 5.20 mm / Pieces - 19 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

5.73 Ct Natural 23 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

5.73 Ct Natural 23 Drilled Multi-color Fire Opal Loose Beads Weight - 5.73 Ct / Size - 4.50 - 5.10 mm / Pieces - 23 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

5.42 Ct Natural 20 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

5.42 Ct Natural 20 Drilled Multi-color Fire Opal Loose Beads Weight - 5.42 Ct / Size - 4.30 - 5.10 mm / Pieces - 20 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

4.09 Ct Natural 73 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

4.09 Ct Natural 73 Drilled Multi-color Fire Opal Loose Beads Weight - 4.09 Ct / Size - 3.00 - 3.30 mm / Pieces - 73 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

4.91 Ct Natural 29 Drilled Multi-color Fire Opal Loose Beads (1 of 3)

4.91 Ct Natural 29 Drilled Multi-color Fire Opal Loose Beads Weight - 4.91 Ct / Size - 3.80 - 4.30 mm / Pieces - 29 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

8.75 Ct Natural 28 Drilled Multi-color Fire Opal Loose Beads (1 of 3)

8.75 Ct Natural 28 Drilled Multi-color Fire Opal Loose Beads Weight - 8.75 Ct / Size - 4.30 - 6.20 mm / Pieces - 28 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

4.28 Ct Natural 12 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

4.28 Ct Natural 12 Drilled Multi-color Fire Opal Loose Beads Weight - 4.28 Ct / Size - 4.80 - 5.10 mm / Pieces - 12 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

4.19 Ct Natural 27 Drilled Multi-color Fire Opal Loose Beads (1 of 3)

4.19 Ct Natural 27 Drilled Multi-color Fire Opal Loose Beads Weight - 4.19 Ct / Size - 3.80 - 4.20 mm / Pieces - 27 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

8.36 Ct Natural 22 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

8.36 Ct Natural 22 Drilled Multi-color Fire Opal Loose Beads Weight - 8.36 Ct / Size - 5.20 - 5.60 mm / Pieces - 22 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

5.80 Ct Natural 23 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

5.80 Ct Natural 23 Drilled Multi-color Fire Opal Loose Beads Weight - 5.80 Ct / Size - 4.30 - 4.80 mm / Pieces - 23 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

8.11 Ct Natural 16 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

8.11 Ct Natural 16 Drilled Multi-color Fire Opal Loose Beads Weight - 8.11 Ct / Size - 5.10 - 6.10 mm / Pieces - 16 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

7.11 Ct Natural 29 Drilled Multi-color Fire Opal Loose Beads (1 of 3)

7.11 Ct Natural 29 Drilled Multi-color Fire Opal Loose Beads Weight - 7.11 Ct / Size - 5.70 - 6.20 mm / Pieces - 18 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Sold

5.44 Ct Natural 9 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

5.44 Ct Natural 9 Drilled Multi-color Fire Opal Loose Beads Weight - 5.44 Ct / Size - 5.50 - 6.00 mm / Pieces - 9 No's / Shape - Round Beads / Color - Multicolor / Clarity - Transparent / Origin - Ethiopia / Treatment - None

See Sold Price

Upcoming Sales

Sort by:

Best Match

3.83 Ct Natural 31 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

3.83 Ct Natural 31 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

5.25 Ct Natural 22 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

5.25 Ct Natural 22 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

5.11 Ct Natural 40 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

5.11 Ct Natural 40 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

3.17 Ct Natural 31 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

3.17 Ct Natural 31 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

6.56 Ct Natural 36 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

6.56 Ct Natural 36 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

1.66 Ct Natural 52 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

1.66 Ct Natural 52 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

3.31 Ct Natural 26 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

3.31 Ct Natural 26 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

3.18 Ct Natural 53 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

3.18 Ct Natural 53 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

8.32 Ct Natural 23 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

8.32 Ct Natural 23 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

5.64 Ct Natural 32 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

5.64 Ct Natural 32 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

3.93 Ct Natural 33 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

3.93 Ct Natural 33 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

5.67 Ct Natural 22 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

5.67 Ct Natural 22 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

3.17 Ct Natural 62 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

3.17 Ct Natural 62 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

5.86 Ct Natural 20 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

5.86 Ct Natural 20 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

2.94 Ct Natural 16 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

2.94 Ct Natural 16 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Feb 28, 2024

3.60 Ct Natural 9 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

3.60 Ct Natural 9 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Mar 13, 2024

4.29 Ct Natural 13 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

4.29 Ct Natural 13 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Mar 13, 2024

83.16 Ct Natural 164 Drilled Multi-color Fire Opal Loose Beads Certified Natural Gemstones (1 of 4)

83.16 Ct Natural 164 Drilled Multi-color Fire Opal Loose Beads Certified Natural Gemstones

See Sold Price

Mar 06, 2024

58.16 Ct Natural 100 Drilled Multi-color Fire Opal Loose Beads Certified Natural Gemstones (1 of 3)

58.16 Ct Natural 100 Drilled Multi-color Fire Opal Loose Beads Certified Natural Gemstones

See Sold Price

Mar 06, 2024

72.33 Ct Natural 171 Drilled Multi-color Fire Opal Loose Beads Certified Natural Gemstones (1 of 3)

72.33 Ct Natural 171 Drilled Multi-color Fire Opal Loose Beads Certified Natural Gemstones

See Sold Price

Mar 06, 2024

66.25 Ct Natural 183 Drilled Multi-color Fire Opal Loose Beads Certified Natural Gemstones (1 of 2)

66.25 Ct Natural 183 Drilled Multi-color Fire Opal Loose Beads Certified Natural Gemstones

See Sold Price

Mar 06, 2024

8.44 Ct Natural 11 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

8.44 Ct Natural 11 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Mar 27, 2024

1.81 Ct Natural 5 Drilled Multi-color Fire Opal Loose Beads (1 of 2)

1.81 Ct Natural 5 Drilled Multi-color Fire Opal Loose Beads

See Sold Price

Mar 27, 2024

40.67 Ct Natural Drilled Multi-color Fire Opal Loose Beads Certified Natural earthmined Gemstones (1 of 2)

40.67 Ct Natural Drilled Multi-color Fire Opal Loose Beads Certified Natural earthmined Gemstones

See Sold Price

Apr 01, 2024

TOP