Dillwynia is a plant genus of the family Fabaceae.
 They are endemic to Australia, occurring in all states except the Northern Territory.
The Mohs scale of mineral hardness is a qualitative ordinal scale characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material.
 Created in 1812 by German geologist and mineralogist Friedrich Mohs, it is one of several definitions of hardness in materials science, some of which are more quantitative.
 The method of comparing hardness by seeing which minerals can visibly scratch others is, however, of great antiquity, having been mentioned by Theophrastus in his treatise "On Stones", c. 300 BC, followed by Pliny the Elder in his "Naturalis Historia", c. 77 AD.
 While greatly facilitating the identification of minerals in the field, the Mohs scale does not show how well hard materials perform in an industrial setting.
Shock hardening is a process used to strengthen metals and alloys, wherein a shock wave produces atomic-scale defects in the material's crystalline structure.
 As in cold work, these defects interfere with the normal processes by which metallic materials yield (plasticity), making materials stiffer, but more brittle.
 When compared to traditional cold work, such an extremely rapid process results in a different class of defect, producing a much harder material for a given change in shape.
 If the shock wave applies too great a force for too long, however, the rarefaction front that follows it can form voids in the material due to hydrostatic tension, weakening the material and often causing it to spall.
 Since voids nucleate at large defects, such as oxide inclusions and grain boundaries, high-purity samples with a large grain size (especially single crystals) are able to withstand greater shock without spalling, and can therefore be made much harder.
A dirt road or track is a type of unpaved road made from the native material of the land surface through which it passes, known to highway engineers as subgrade material.
 Dirt roads are suitable for vehicles; a narrower path for pedestrians, animals, and possibly small vehicles would be called a dirt track—the distinction is not well-defined.
 Unpaved roads with a harder surface made by the addition of material such as gravel and aggregate (stones), might be referred to as dirt roads in common usage but are distinguished as improved roads by highway engineers.
 (Improved unpaved roads include gravel roads, laterite roads, murram roads and macadamized roads.)
A yardang is a streamlined protuberance carved from bedrock or any consolidated or semiconsolidated material by the dual action of wind abrasion by dust and sand, and deflation which is the removal of loose material by wind turbulence.
 Yardangs become elongated features typically three or more times longer than wide, and when viewed from above, resemble the hull of a boat.
 Facing the wind is a steep, blunt face that gradually gets lower and narrower toward the lee end.
 Yardangs are formed by wind erosion, typically of an originally flat surface formed from areas of harder and softer material.
 The soft material is eroded and removed by the wind, and the harder material remains.
 The resulting pattern of yardangs is therefore a combination of the original rock distribution, and the fluid mechanics of the air flow and resulting pattern of erosion.
Aluminium oxynitride or AlON is a ceramic composed of aluminium, oxygen and nitrogen.
 It is marketed under the name ALON by Surmet Corporation.
 AlON is optically transparent (≥80%) in the near-ultraviolet, visible and midwave-infrared regions of the electromagnetic spectrum.
 It is 4 times harder than fused silica glass, 85% as hard as sapphire, and nearly 15% harder than magnesium aluminate spinel.
 Since it has a cubic spinel structure, it can be fabricated to transparent windows, plates, domes, rods, tubes and other forms using conventional ceramic powder processing techniques.
 ALON is the hardest polycrystalline transparent ceramic available commercially.
 Combination of optical and mechanical properties makes this material a leading candidate for lightweight high-performance transparent armor applications such as bulletproof and blast-resistant windows and for many military infrared optics.
 AlON-based armor has been shown to stop multiple armor-piercing projectiles of up to 50 cal.
 It is commercially available in sizes as big as 18x35-inch monolithic windows.
A string puzzle is any mechanical puzzle where the emphasis is on manipulating one or more pieces of string or rope.
 The string(s) may be closed loops or unclosed or fixed to some given harder material in a certain way.
 Usually there is only one piece of rope or string.
 The string may have balls or similar attached to its ends.
 There may also be a ring or similar sliding along the string.
Mischmetal (from German: "Mischmetall" – "mixed metal") is an alloy of rare-earth elements.
 It is also called cerium mischmetal, rare-earth mischmetal or misch metal.
 A typical composition includes approximately 50% cerium and 25% lanthanum, with small amounts of neodymium and praseodymium.
 Its most common use is in the ferrocerium "flint" ignition device of many lighters and torches, although an alloy of only rare-earth elements would be too soft to give good sparks.
 For this purpose, it is blended with iron oxide and magnesium oxide to form a harder material known as ferrocerium.
 In chemical formulae it is commonly abbreviated as Mm, e.g. MmNi.
Quirinus Johan Harder (13 October 1801, Rotterdam - 21 October 1880, Vlissingen) was a Dutch architect best known for having designed a large number of lighthouses.
 He worked as a structural engineer for the , the Dutch organization overseeing all maritime pilots. Harder's lighthouses were made of cast iron, a new material at the time, which allowed for segmented fabrication and construction.
An arrowhead is a tip, usually sharpened, added to an arrow to make it more deadly or to fulfill some special purpose.
 The earliest arrowheads were made of stone and of organic materials; as human civilization progressed other materials were used.
 Arrowheads are important archaeological artifacts; they are a subclass of projectile points. Modern enthusiasts still "produce over one million brand-new spear and arrow points per year".

Question:  Is Dillwynia made of a harder material than an Arrowhead?
Answer: no