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Casio Master Of G - Land Mudmaster 58.7mm Mens Watch
Ref. GWG-B1000MG-1A9ER
Sits in Casio’s upper tier here — more premium than three quarters of the Casio watches we list, which start at £25.
Price range £25 to £919 across 136 Casio watches in stock.The Magma Gold Mudmaster marks forty years of G-Shock with a design drawn directly from volcanology — the red-orange dial accents follow cooling lava as it shifts toward gold, and the marbled band reads as geological strata rather than surface decoration. Ion-plated components in layered gold tones carry the theme through without overwhelming the underlying purpose of the watch, which remains a working instrument for demanding outdoor conditions. At 52.1mm across the case and 16.2mm thick, this is an unambiguously large watch, but the carbon fibre-reinforced bio-based resin construction brings the whole thing in at 114g — considerably lighter than the dimensions suggest, and noticeably so after an hour on the wrist. The triple sensor suite covers compass bearing, altitude, barometric pressure and temperature, and the Location Indicator function can use a paired smartphone to point the analogue hand toward a set destination — useful when visibility collapses. Atomic sync across six radio bands and Bluetooth keep the time honest without intervention.
- Reference
- GWG-B1000MG-1A9ER
- Brand
- Casio
- Collection
- G-SHOCK Master of G
- Case size
- 58.7mm
- Case material
- Stainless steel
- Case shape
- Round
- Dial
- Black
- Crystal
- Sapphire
- Movement
- Solar
- Functions
- Stopwatch, Countdown timer, Alarm, Backlight, World time, Solar powered, Radio controlled, Bluetooth, Compass, Thermometer, Altimeter, Dual display, Digital display
- Water resistance
- 200m
- Bracelet / strap
- Rubber strap
- Strap colour
- Black
- Clasp
- Buckle
- Lume
- Luminous
- Retailer
- Goldsmiths
Additional specifications
- Origin
- Made in Japan
Learn more about Casio
Tadao Kashio founded Kashio Seisakujo in Tokyo in 1946 as a machine shop. The company's first success was a finger ring that held a cigarette, and its second was the 14-A of 1957 — the world's first all-electric compact calculator, which used solenoids rather than gears.
Casio entered watchmaking in 1974 with the Casiotron, a digital watch with an automatic calendar that knew the varying lengths of months. The company approached watches as an electronics manufacturer rather than a horological one, and that difference produced the G-Shock.
The G-Shock came from a single engineer, Kikuo Ibe, who broke a watch his father had given him and set out to build one that could not break. The specification was three tens: survive a ten-metre drop, ten bars of water pressure, and ten years of battery life. It took over two hundred prototypes, and the solution was suspending the module inside the case on a cushioned internal structure rather than mounting it rigidly. The DW-5000C shipped in 1983.
It became one of the most durable product designs in any category, adopted by militaries, emergency services, and skateboarders alike, and Casio has since added solar charging, radio and GPS timekeeping, Bluetooth, and full-metal and carbon variants.
Casio also produces the Edifice, Pro Trek, and Oceanus lines, and remains an independent Japanese public company.
- 1946
- Tadao Kashio founds the company in Tokyo.
- 1974
- The Casiotron is Casio's first digital watch.
- 1983
- The G-Shock DW-5000C survives Kikuo Ibe's three-tens brief.
- 1994
- The Frogman extends G-Shock to ISO dive certification.
Also in 6 collections
This watch appears in Back in Stock (4,683), Stainless Steel Watches (3,109), Watches 44mm and Over (827), Sports Watches (800), Dive Watches (568) and All Black Watches (315).
Manufacturer’s guarantee
What the specifications mean
A watch built to be worn hard and got wet.
Strengths
- 200m water resistance, rated for actual diving
- Sapphire crystal, which resists scratching
- Luminous hands and markers for low light
- Second time zone for travelling
- One of Casio's more premium watches
Worth knowing
- 58.7mm is a large watch with real presence
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Yes. At 200m it is rated for swimming, snorkelling and recreational diving.
Water resistance explainedWill the glass scratch?
Unlikely. Sapphire is second only to diamond in hardness and shrugs off everyday marking.
Sapphire, mineral and acrylic comparedDoes it need a battery?
No. It charges from light, and the cell behind that is designed to last a decade or more.
Quartz, automatic and solar comparedIs it a men's or women's watch?
Listed as men's.
Cheapest place to buy
Goldsmiths is the only UK retailer we track stocking this reference, so there is nothing to compare it against today.
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